土木工程外文翻译经典
土木工程毕业设计外文翻译原文+翻译
The bridge crack produced the reason to simply analyseIn recent years, the traffic capital construction of our province gets swift and violent development, all parts have built a large number of concrete bridges. In the course of building and using in the bridge, relevant to influence project quality lead of common occurrence report that bridge collapse even because the crack appears The concrete can be said to " often have illness coming on " while fracturing and " frequently-occurring disease ", often perplex bridge engineers and technicians. In fact , if take certain design and construction measure, a lot of cracks can be overcome and controlled. For strengthen understanding of concrete bridge crack further, is it prevent project from endanger larger crack to try one's best, this text make an more overall analysis , summary to concrete kind and reason of production , bridge of crack as much as possible, in order to design , construct and find out the feasible method which control the crack , get the result of taking precautions against Yu WeiRan.Concrete bridge crack kind, origin cause of formation In fact, the origin cause of formation of the concrete structure crack is complicated and various, even many kinds of factors influence each other , but every crack has its one or several kinds of main reasons produced . The kind of the concrete bridge crack, on its reason to produce, can roughly divide several kinds as follows :(1) load the crack caused Concrete in routine quiet .Is it load to move and crack that produce claim to load the crack under the times of stress bridge, summing up has direct stress cracks , two kinds stress crack onces mainly. Direct stress crack refer to outside load direct crack that stress produce that cause. The reason why the crack produces is as follows, 1, Design the stage of calculating , does not calculate or leaks and calculates partly while calculating in structure; Calculate the model is unreasonable; The structure is supposed and accorded with by strength actually by strength ; Load and calculate or leak and calculate few; Internal force and matching the mistake in computation of muscle; Safety coefficient of structure is not enough. Do not consider the possibility that construct at the time of the structural design; It is insufficientto design the section; It is simply little and assigning the mistake for reinforcing bar to set up; Structure rigidity is insufficient; Construct and deal with improperly; The design drawing can not be explained clearly etc.. 2, Construction stage, does not pile up and construct the machines , material limiting ; Is it prefabricate structure structure receive strength characteristic , stand up , is it hang , transport , install to get up at will to understand; Construct not according to the design drawing, alter the construction order of the structure without authorization , change the structure and receive the strength mode; Do not do the tired intensity checking computations under machine vibration and wait to the structure . 3, Using stage, the heavy-duty vehicle which goes beyond the design load passes the bridge; Receive the contact , striking of the vehicle , shipping; Strong wind , heavy snow , earthquake happen , explode etc.. Stress crack once means the stress of secondary caused by loading outside produces the crack. The reason why the crack produces is as follows, 1, In design outside load function , because actual working state and routine , structure of thing calculate have discrepancy or is it consider to calculate, thus cause stress once to cause the structure to fracture in some position. Two is it join bridge arch foot is it is it assign " X " shape reinforcing bar , cut down this place way , section of size design and cut with scissors at the same time to adopt often to design to cut with scissors, theory calculate place this can store curved square in , but reality should is it can resist curved still to cut with scissors, so that present the crack and cause the reinforcing bar corrosion. 2, Bridge structure is it dig trough , turn on hole , set up ox leg ,etc. to need often, difficult to use a accurate one diagrammatic to is it is it calculate to imitate to go on in calculating in routine, set up and receive the strength reinforcing bar in general foundation experience. Studies have shown , after being dug the hole by the strength component , it will produce the diffraction phenomenon that strength flows, intensive near the hole in a utensil, produced the enormous stress to concentrate. In long to step prestressing force of the continuous roof beam , often block the steel bunch according to the needs of section internal force in stepping, set up the anchor head, but can often see the crack in the anchor firm section adjacent place. So if deal with improper, in corner or component form sudden change office , block place to be easy to appear crack strengthreinforcing bar of structure the. In the actual project, stress crack once produced the most common reason which loads the crack. Stress crack once belong to one more piece of nature of drawing , splitting off , shearing. Stress crack once is loaded and caused, only seldom calculate according to the routine too, but with modern to calculate constant perfection of means, times of stress crack to can accomplish reasonable checking computations too. For example to such stresses 2 times of producing as prestressing force , creeping ,etc., department's finite element procedure calculates levels pole correctly now, but more difficult 40 years ago. In the design, should pay attention to avoiding structure sudden change (or section sudden change), when it is unable to avoid , should do part deal with , corner for instance, make round horn , sudden change office make into the gradation zone transition, is it is it mix muscle to construct to strengthen at the same time, corner mix again oblique to reinforcing bar , as to large hole in a utensil can set up protecting in the perimeter at the terms of having angle steel. Load the crack characteristic in accordance with loading differently and presenting different characteristics differently. The crack appear person who draw more, the cutting area or the serious position of vibration. Must point out , is it get up cover or have along keep into short crack of direction to appear person who press, often the structure reaches the sign of bearing the weight of strength limit, it is an omen that the structure is destroyed, its reason is often that sectional size is partial and small. Receive the strength way differently according to the structure, the crack characteristic produced is as follows: 1, The centre is drawn. The crack runs through the component cross section , the interval is equal on the whole , and is perpendicular to receiving the strength direction. While adopting the whorl reinforcing bar , lie in the second-class crack near the reinforcing bar between the cracks. 2, The centre is pressed. It is parallel on the short and dense parallel crack which receive the strength direction to appear along the component. 3, Receive curved. Most near the large section from border is it appear and draw into direction vertical crack to begin person who draw curved square, and develop toward neutralization axle gradually. While adopting the whorl reinforcing bar , can see shorter second-class crack among the cracks. When the structure matches muscles less, there are few but wide cracks, fragility destruction may take place in thestructure 4, Pressed big and partial. Heavy to press and mix person who draw muscle a less one light to pigeonhole into the component while being partial while being partial, similar to receiving the curved component. 5, Pressed small and partial. Small to press and mix person who draw muscle a more one heavy to pigeonhole into the component while being partial while being partial, similar to the centre and pressed the component. 6, Cut. Press obliquly when the hoop muscle is too dense and destroy, the oblique crack which is greater than 45?? direction appears along the belly of roof beam end; Is it is it is it destroy to press to cut to happen when the hoop muscle is proper, underpart is it invite 45?? direction parallel oblique crack each other to appear along roof beam end. 7, Sprained. Component one side belly appear many direction oblique crack, 45?? of treaty, first, and to launch with spiral direction being adjoint. 8, Washed and cut. 4 side is it invite 45?? direction inclined plane draw and split to take place along column cap board, form the tangent plane of washing. 9, Some and is pressed. Some to appear person who press direction roughly parallel large short cracks with pressure.(2) crack caused in temperature changeThe concrete has nature of expanding with heat and contract with cold, look on as the external environment condition or the structure temperature changes, concrete take place out of shape, if out of shape to restrain from, produce the stress in the structure, produce the temperature crack promptly when exceeding concrete tensile strength in stress. In some being heavy to step foot-path among the bridge , temperature stress can is it go beyond living year stress even to reach. The temperature crack distinguishes the main characteristic of other cracks will be varied with temperature and expanded or closed up. The main factor is as follows, to cause temperature and change 1, Annual difference in temperature. Temperature is changing constantly in four seasons in one year, but change relatively slowly, the impact on structure of the bridge is mainly the vertical displacement which causes the bridge, can prop up seat move or set up flexible mound ,etc. not to construct measure coordinate , through bridge floor expansion joint generally, can cause temperature crack only when the displacement of the structure is limited, for example arched bridge , just bridge etc. The annual difference in temperature of our country generally changes therange with the conduct of the average temperature in the moon of January and July. Considering the creep characteristic of the concrete, the elastic mould amount of concrete should be considered rolling over and reducing when the internal force of the annual difference in temperature is calculated. 2, Rizhao. After being tanned by the sun by the sun to the side of bridge panel , the girder or the pier, temperature is obviously higher than other position, the temperature gradient is presented and distributed by the line shape . Because of restrain oneself function, cause part draw stress to be relatively heavy, the crack appears. Rizhao and following to is it cause structure common reason most , temperature of crack to lower the temperature suddenly 3, Lower the temperature suddenly. Fall heavy rain , cold air attack , sunset ,etc. can cause structure surface temperature suddenly dropped suddenly, but because inside temperature change relatively slow producing temperature gradient. Rizhao and lower the temperature internal force can adopt design specification or consult real bridge materials go on when calculating suddenly, concrete elastic mould amount does not consider converting into and reducing 4, Heat of hydration. Appear in the course of constructing, the large volume concrete (thickness exceeds 2. 0), after building because cement water send out heat, cause inside very much high temperature, the internal and external difference in temperature is too large, cause the surface to appear in the crack. Should according to actual conditions in constructing, is it choose heat of hydration low cement variety to try one's best, limit cement unit's consumption, reduce the aggregate and enter the temperature of the mould , reduce the internal and external difference in temperature, and lower the temperature slowly , can adopt the circulation cooling system to carry on the inside to dispel the heat in case of necessity, or adopt the thin layer and build it in succession in order to accelerate dispelling the heat. 5, The construction measure is improper at the time of steam maintenance or the winter construction , the concrete is sudden and cold and sudden and hot, internal and external temperature is uneven , apt to appear in the crack. 6, Prefabricate T roof beam horizontal baffle when the installation , prop up seat bury stencil plate with transfer flat stencil plate when welding in advance, if weld measure to be improper, iron pieces of nearby concrete easy to is it fracture to burn. Adopt electric heat piece draw law piece draw prestressing force at the component ,prestressing force steel temperature can rise to 350 degrees Centigrade , the concrete component is apt to fracture. Experimental study indicates , are caused the intensity of concrete that the high temperature burns to obviously reduce with rising of temperature by such reasons as the fire ,etc., glueing forming the decline thereupon of strength of reinforcing bar and concrete, tensile strength drop by 50% after concrete temperature reaches 300 degrees Centigrade, compression strength drops by 60%, glueing the strength of forming to drop by 80% of only round reinforcing bar and concrete; Because heat, concrete body dissociate ink evaporate and can produce and shrink sharply in a large amount(3) shrink the crack causedIn the actual project, it is the most common because concrete shrinks the crack caused. Shrink kind in concrete, plasticity shrink is it it shrinks (is it contract to do ) to be the main reason that the volume of concrete out of shape happens to shrink, shrink spontaneously in addition and the char shrink. Plasticity shrink. About 4 hours after it is built that in the course of constructing , concrete happens, the cement water response is fierce at this moment, the strand takes shape gradually, secrete water and moisture to evaporate sharply, the concrete desiccates and shrinks, it is at the same time conduct oneself with dignity not sinking because aggregate,so when harden concrete yet,it call plasticity shrink. The plasticity shrink producing amount grade is very big, can be up to about 1%. If stopped by the reinforcing bar while the aggregate sinks, form the crack along the reinforcing bar direction. If web , roof beam of T and roof beam of case and carry baseplate hand over office in component vertical to become sectional place, because sink too really to superficial obeying the web direction crack will happen evenly before hardenning. For reducing concrete plasticity shrink,it should control by water dust when being construct than,last long-time mixing, unloading should not too quick, is it is it take closely knit to smash to shake, vertical to become sectional place should divide layer build. Shrink and shrink (do and contract). After the concrete is formed hard , as the top layer moisture is evaporated progressively , the humidity is reduced progressively , the volume of concrete is reduced, is called and shrunk to shrink (do and contract). Because concrete top layermoisture loss soon, it is slow for inside to lose, produce surface shrink heavy , inside shrink a light one even to shrink, it is out of shape to restrain from by the inside concrete for surface to shrink, cause the surface concrete to bear pulling force, when the surface concrete bears pulling force to exceed its tensile strength, produce and shrink the crack. The concrete hardens after-contraction to just shrink and shrink mainly .Such as mix muscle rate heavy component (exceed 3% ), between reinforcing bar and more obvious restraints relatively that concrete shrink, the concrete surface is apt to appear in the full of cracks crackle. Shrink spontaneously. Spontaneous to it shrinks to be concrete in the course of hardenning , cement and water take place ink react, the shrink with have nothing to do by external humidity, and can positive (whether shrink, such as ordinary portland cement concrete), can negative too (whether expand, such as concrete, concrete of slag cement and cement of fly ash). The char shrinks. Between carbon dioxide and hyrate of cement of atmosphere take place out of shape shrink that chemical reaction cause. The char shrinks and could happen only about 50% of humidity, and accelerate with increase of the density of the carbon dioxide. The char shrinks and seldom calculates . The characteristic that the concrete shrinks the crack is that the majority belongs to the surface crack, the crack is relatively detailed in width , and criss-cross, become the full of cracks form , the form does not have any law . Studies have shown , influence concrete shrink main factor of crack as follows, 1, Variety of cement , grade and consumption. Slag cement , quick-hardening cement , low-heat cement concrete contractivity are relatively high, ordinary cement , volcanic ash cement , alumina cement concrete contractivity are relatively low. Cement grade low in addition, unit volume consumption heavy rubing detailed degree heavy, then the concrete shrinks the more greatly, and shrink time is the longer. For example, in order to improve the intensity of the concrete , often adopt and increase the cement consumption method by force while constructing, the result shrinks the stress to obviously strengthen . 2, Variety of aggregate. Such absorbing water rates as the quartz , limestone , cloud rock , granite , feldspar ,etc. are smaller, contractivity is relatively low in the aggregate; And such absorbing water rates as the sandstone , slate , angle amphibolite ,etc. are greater, contractivity is relatively high. Aggregate grains of foot-path heavy to shrink light inaddition, water content big to shrink the larger. 3, Water gray than. The heavier water consumption is, the higher water and dust are, the concrete shrinks the more greatly. 4, Mix the pharmaceutical outside. It is the better to mix pharmaceutical water-retaining property outside, then the concrete shrinks the smaller. 5, Maintain the method . Water that good maintenance can accelerate the concrete reacts, obtain the intensity of higher concrete. Keep humidity high , low maintaining time to be the longer temperature when maintaining, then the concrete shrinks the smaller. Steam maintain way than maintain way concrete is it take light to shrink naturall. 6, External environment. The humidity is little, the air drying , temperature are high, the wind speed is large in the atmosphere, then the concrete moisture is evaporated fast, the concrete shrinks the faster. 7, Shake and smash the way and time. Machinery shake way of smashing than make firm by ramming or tamping way concrete contractivity take little by hand. Shaking should determine according to mechanical performance to smash time , are generally suitable for 55s / time. It is too short, shake and can not smash closely knit , it is insufficient or not even in intensity to form the concrete; It is too long, cause and divide storey, thick aggregate sinks to the ground floor, the upper strata that the detailed aggregate stays, the intensity is not even , the upper strata incident shrink the crack. And shrink the crack caused to temperature, worthy of constructing the reinforcing bar againing can obviously improve the resisting the splitting of concrete , structure of especially thin wall (thick 200cm of wall ). Mix muscle should is it adopt light diameter reinforcing bar (8 |? construct 14 |? ) to have priority , little interval assign (whether @ 10 construct @ 15cm ) on constructing, the whole section is it mix muscle to be rate unsuitable to be lower than 0 to construct. 3%, can generally adopt 0 . 3%~0. 5%.(4), crack that causes out of shape of plinth of the groundBecause foundation vertical to even to subside or horizontal direction displacement, make the structure produce the additional stress, go beyond resisting the ability of drawing of concrete structure, cause the structure to fracture. The even main reason that subside of the foundation is as follows, 1, Reconnoitres the precision and is not enough for , test the materials inaccuratly in geology. Designing, constructing without fully grasping the geological situation, this is the main reason that cause the ground not to subside evenly .Such as hills area or bridge, district of mountain ridge,, hole interval to be too far when reconnoitring, and ground rise and fall big the rock, reconnoitring the report can't fully reflect the real geological situation . 2, The geological difference of the ground is too large. Building it in the bridge of the valley of the ditch of mountain area, geology of the stream place and place on the hillside change larger, even there are weak grounds in the stream, because the soil of the ground does not causes and does not subside evenly with the compressing. 3, The structure loads the difference too big. Under the unanimous terms, when every foundation too heavy to load difference in geological situation, may cause evenly to subside, for example high to fill out soil case shape in the middle part of the culvert than to is it take heavy to load both sides, to subside soon heavy than both sides middle part, case is it might fracture to contain 4, The difference of basic type of structure is great. Unite it in the bridge the samly , mix and use and does not expand the foundation and a foundation with the foundation, or adopt a foundation when a foot-path or a long difference is great at the same time , or adopt the foundation of expanding when basis elevation is widely different at the same time , may cause the ground not to subside evenly too 5, Foundation built by stages. In the newly-built bridge near the foundation of original bridge, if the half a bridge about expressway built by stages, the newly-built bridge loads or the foundation causes the soil of the ground to consolidate again while dealing with, may cause and subside the foundation of original bridge greatly 6, The ground is frozen bloatedly. The ground soil of higher moisture content on terms that lower than zero degree expands because of being icy; Once temperature goes up , the frozen soil is melted, the setting of ground. So the ground is icy or melts causes and does not subside evenly . 7, Bridge foundation put on body, cave with stalactites and stalagmites, activity fault,etc. of coming down at the bad geology, may cause and does not subside evenly . 8, After the bridge is built up , the condition change of original ground . After most natural grounds and artificial grounds are soaked with water, especially usually fill out such soil of special ground as the soil , loess , expanding in the land ,etc., soil body intensity meet water drop, compress out of shape to strengthen. In the soft soil ground , season causes the water table to drop to draw water or arid artificially, the ground soil layer consolidates and sinks again,reduce the buoyancy on the foundation at the same time , shouldering the obstruction of rubing to increase, the foundation is carried on one's shoulder or back and strengthened .Some bridge foundation is it put too shallow to bury, erode , is it dig to wash flood, the foundation might be moved. Ground load change of terms, bridge nearby is it is it abolish square , grit ,etc. in a large amount to put to pile with cave in , landslide ,etc. reason for instance, it is out of shape that the bridge location range soil layer may be compressed again. So, the condition of original ground change while using may cause and does not subside evenly Produce the structure thing of horizontal thrust to arched bridge ,etc., it is the main reason that horizontal displacement crack emerges to destroy the original geological condition when to that it is unreasonable to grasp incompletely , design and construct in the geological situation.桥梁裂缝产生原因浅析近年来，我省交通基础建设得到迅猛发展，各地建立了大量的混凝土桥梁。
(完整)土木工程外文翻译
原文Prestressed ConcreteConcrete is strong in compression， but weak in tension： Its tensile strength varies from 8 to 14 percent of its compressive strength。
Due to such a low tensile capacity， flexural cracks develop at early stages of loading. In order to reduce or prevent such cracks from developing， a concentric or eccentric force is imposed in the longitudinal direction of the structural element. This force prevents the cracks from developing by eliminating or considerably reducing the tensile stresses at the critical midspan and support sections at service load, thereby raising the bending, shear， and torsional capacities of the sections。
The sections are then able to behave elastically， and almost the full capacity of the concrete in compression can be efficiently utilized across the entire depth of the concrete sections when all loads act on the structure.Such an imposed longitudinal force is called a prestressing force， i.e., a compressive force that prestresses the sections along the span of the structural element prior to the application of the transverse gravity dead and live loads or transient horizontal live loads。
土木工程英文文献及翻译
Civil engineeringCivil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including works like bridges, roads, canals, dams, and buildings.[1][2][3] Civil engineering is the oldest engineering discipline after military engineering,[4] and it was defined to distinguish non-military engineering from military engineering.[5] It is traditionally broken into several sub-disciplines including environmental engineering, geotechnical engineering, structural engineering, transportation engineering, municipal or urban engineering, water resources engineering, materials engineering, coastal engineering,[4] surveying, and construction engineering.[6] Civil engineering takes place on all levels: in the public sector from municipal through to national governments, and in the private sector from individual homeowners through to international companies.History of the civil engineering professionSee also: History of structural engineeringEngineering has been an aspect of life since the beginnings of human existence. The earliest practices of Civil engineering may have commenced between 4000 and 2000 BC in Ancient Egypt and Mesopotamia (Ancient Iraq) when humans started to abandon a nomadic existence, thus causing a need for the construction of shelter. During this time, transportation became increasingly important leading to the development of the wheel and sailing.Until modern times there was no clear distinction between civil engineering and architecture, and the term engineer and architect were mainly geographical variations referring to the same person, often used interchangeably.[7]The construction of Pyramids in Egypt (circa 2700-2500 BC) might be considered the first instances of large structure constructions. Other ancient historic civil engineering constructions include the Parthenon by Iktinos in Ancient Greece (447-438 BC), theAppian Way by Roman engineers (c. 312 BC), the Great Wall of China by General Meng T'ien under orders from Ch'in Emperor Shih Huang Ti (c. 220 BC)[6] and the stupas constructed in ancient Sri Lanka like the Jetavanaramaya and the extensive irrigation works in Anuradhapura. The Romans developed civil structures throughout their empire, including especially aqueducts, insulae, harbours, bridges, dams and roads.In the 18th century, the term civil engineering was coined to incorporate all things civilian as opposed to military engineering.[5]The first self-proclaimed civil engineer was John Smeaton who constructed the Eddystone Lighthouse.[4][6]In 1771 Smeaton and some of his colleagues formed the Smeatonian Society of Civil Engineers, a group of leaders of the profession who met informally over dinner. Though there was evidence of some technical meetings, it was little more than a social society.In 1818 the Institution of Civil Engineers was founded in London, and in 1820 the eminent engineer Thomas Telford became its first president. The institution received a Royal Charter in 1828, formally recognising civil engineering as a profession. Its charter defined civil engineering as:the art of directing the great sources of power in nature for the use and convenience of man, as the means of production and of traffic in states, both for external and internal trade, as applied in the construction of roads, bridges, aqueducts, canals, river navigation and docks for internal intercourse and exchange, and in the construction of ports, harbours, moles, breakwaters and lighthouses, and in the art of navigation by artificial power for the purposes of commerce, and in the construction and application of machinery, and in the drainage of cities and towns.[8] The first private college to teach Civil Engineering in the United States was Norwich University founded in 1819 by Captain Alden Partridge.[9] The first degree in Civil Engineering in the United States was awarded by Rensselaer Polytechnic Institute in 1835.[10] The first such degree to be awarded to a woman was granted by Cornell University to Nora Stanton Blatchin 1905.History of civil engineeringCivil engineering is the application of physical and scientific principles, and its history is intricately linked to advances in understanding of physics and mathematics throughout history. Because civil engineering is a wide ranging profession, including several separate specialized sub-disciplines, its history is linked to knowledge of structures, materials science, geography, geology, soils, hydrology, environment, mechanics and other fields.Throughout ancient and medieval history most architectural design and construction was carried out by artisans, such as stone masons and carpenters, rising to the role of master builder. Knowledge was retained in guilds and seldom supplanted by advances. Structures, roads and infrastructure that existed were repetitive, and increases in scale were incremental.[12]One of the earliest examples of a scientific approach to physical and mathematical problems applicable to civil engineering is the work of Archimedes in the 3rd century BC, including Archimedes Principle, which underpins our understanding of buoyancy, and practical solutions such as Archimedes' screw. Brahmagupta, an Indian mathematician, used arithmetic in the 7th century AD, based on Hindu-Arabic numerals, for excavation (volume) computations.[13]Civil engineers typically possess an academic degree with a major in civil engineering. The length of study for such a degree is usually three to five years and the completed degree is usually designated as a Bachelor of Engineering, though some universities designate the degree as a Bachelor of Science. The degree generally includes units covering physics, mathematics, project management, design and specific topics in civil engineering. Initially such topics cover most, if not all, of thesub-disciplines of civil engineering. Students then choose to specialize in one or more sub-disciplines towards the end of the degree.[14]While anUndergraduate (BEng/BSc) Degree will normally provide successful students with industry accredited qualification, some universities offer postgraduate engineering awards (MEng/MSc) which allow students to further specialize in their particular area of interest within engineering.[15]In most countries, a Bachelor's degree in engineering represents the first step towards professional certification and the degree program itself is certified by a professional body. After completing a certified degree program the engineer must satisfy a range of requirements (including work experience and exam requirements) before being certified. Once certified, the engineer is designated the title of Professional Engineer (in the United States, Canada and South Africa), Chartered Engineer (in most Commonwealth countries), Chartered Professional Engineer (in Australia and New Zealand), or European Engineer (in much of the European Union). There are international engineering agreements between relevant professional bodies which are designed to allow engineers to practice across international borders.The advantages of certification vary depending upon location. For example, in the United States and Canada "only a licensed engineer may prepare, sign and seal, and submit engineering plans and drawings to a public authority for approval, or seal engineering work for public and private clients.".[16]This requirement is enforced by state and provincial legislation such as Quebec's Engineers Act.[17]In other countries, no such legislation exists. In Australia, state licensing of engineers is limited to the state of Queensland. Practically all certifying bodies maintain a code of ethics that they expect all members to abide by or risk expulsion.[18] In this way, these organizations play an important role in maintaining ethical standards for the profession. Even in jurisdictions where certification has little or no legal bearing on work, engineers are subject to contract law. In cases where an engineer's work fails he or she may be subject to the tort of negligence and, in extreme cases, thecharge of criminal negligence.[citation needed] An engineer's work must also comply with numerous other rules and regulations such as building codes and legislation pertaining to environmental law.CareersThere is no one typical career path for civil engineers. Most people who graduate with civil engineering degrees start with jobs that require a low level of responsibility, and as the new engineers prove their competence, they are trusted with tasks that have larger consequences and require a higher level of responsibility. However, within each branch of civil engineering career path options vary. In some fields and firms, entry-level engineers are put to work primarily monitoring construction in the field, serving as the "eyes and ears" of senior design engineers; while in other areas, entry-level engineers perform the more routine tasks of analysis or design and interpretation. Experienced engineers generally do more complex analysis or design work, or management of more complex design projects, or management of other engineers, or into specialized consulting, including forensic engineering.In general, civil engineering is concerned with the overall interface of human created fixed projects with the greater world. General civil engineers work closely with surveyors and specialized civil engineers to fit and serve fixed projects within their given site, community and terrain by designing grading, drainage, pavement, water supply, sewer service, electric and communications supply, and land divisions. General engineers spend much of their time visiting project sites, developing community consensus, and preparing construction plans. General civil engineering is also referred to as site engineering, a branch of civil engineering that primarily focuses on converting a tract of land from one usage to another. Civil engineers typically apply the principles of geotechnical engineering, structural engineering, environmental engineering, transportation engineering and construction engineering toresidential, commercial, industrial and public works projects of all sizes and levels of construction翻译：土木工程土木工程是一个专业的工程学科，包括设计，施工和维护与环境的改造，涉及了像桥梁，道路，河渠，堤坝和建筑物工程交易土木工程是最古老的军事工程后，工程学科，它被定义为区分军事工程非军事工程的学科它传统分解成若干子学科包括环境工程，岩土工程，结构工程，交通工程，市或城市工程，水资源工程，材料工程，海岸工程，勘测和施工工程等土木工程的范围涉及所有层次：从市政府到国家，从私人部门到国际公司。
土木工程专业外文文献及翻译
英文原文：Building construction concrete crack ofprevention and processingAbstractThe crack problem of concrete is a widespread existence but again difficult in solve of engineering actual problem, this text carried on a study analysis to a little bit familiar crack problem in the concrete engineering, and aim at concrete the circumstance put forward some prevention, processing measure.Keyword: Concrete crack prevention processingForewordConcrete's is 1 kind is anticipate by the freestone bone, cement, water and other mixture but formation of the in addition material of quality brittleness not and all material. Because the concrete construction transform with oneself, control etc. a series problem, harden model of in the concrete existence numerous tiny hole, spirit cave and tiny crack, is exactly because these beginning start blemish of existence just make the concrete present one some not and all the characteristic of quality. The tiny crack is a kind of harmless crack and accept concrete heavy, defend Shen and a little bit other use function not a creation to endanger. But after the concrete be subjected to lotus carry, difference in temperature etc. function, tiny crack would continuously of expand with connect, end formation we can see without the aid of instruments of macro view the crack be also the crack that the concrete often say in the engineering.Concrete building and Gou piece usually all take sewer to make of, because of crack of existence and development usually make inner part of reinforcing bar etc. material creation decay, lower reinforced concrete material of loading ability, durable and anti- Shen ability, influence building of external appearance, service life, severity will threat arrive people's life and property safety. A lot of all of crash of engineerings is because of the unsteady development of the crack with the resultthat. Modern age science research with a great deal of of the concrete engineering practice certificate, in the concrete engineering crack problem is ineluctable, also acceptable in certainly of the scope just need to adopt valid of measure will it endanger degree control at certain of scope inside. The reinforced concrete norm is also explicit provision: Some structure at place of dissimilarity under the condition allow existence certain the crack of width. But at under construction should as far as possible adopt a valid measure control crack creation, make the structure don't appear crack possibly or as far as possible decrease crack of amount and width, particularly want to as far as possible avoid harmful crack of emergence, insure engineering quality thus.Concrete crack creation of the reason be a lot of and have already transformed to cause of crack: Such as temperature variety, constringency, inflation, the asymmetry sink to sink etc. reason cause of crack; Have outside carry the crack that the function cause; Protected environment not appropriate the crack etc. caused with chemical effect. Want differentiation to treat in the actual engineering, workout a problem according to the actual circumstance.In the concrete engineering the familiar crack and the prevention1.Stem Suo crack and preventionStem the Suo crack much appear after the concrete protect be over of a period of time or concrete sprinkle to build to complete behind of around a week. In the cement syrup humidity of evaporate would creation stem Suo, and this kind of constringency is can't negative. Stem Suo crack of the creation be main is because of concrete inside outside humidity evaporate degree dissimilarity but cause to transform dissimilarity of result: The concrete is subjected to exterior condition of influence, surface humidity loss lead quick, transform bigger, inner part degree of humidity variety smaller transform smaller, bigger surface stem the Suo transform to be subjected to concrete inner part control, creation more big pull should dint but creation crack. The relative humidity is more low, cement syrup body stem Suo more big, stem the Suo crack be more easy creation. Stem the Suo crack is much surface parallel lines form or the net shallow thin crack, width many between 0.05-0.2 mm,the flat surface part much see in the big physical volume concrete and follow it more in thinner beam plank short to distribute. Stem Suo crack usually the anti- Shen of influence concrete, cause the durable of the rust eclipse influence concrete of reinforcing bar, under the function of the water pressure dint would creation the water power split crack influence concrete of loading dint etc..Concrete stem the Suo be main with water ash of the concrete ratio, the dosage of the composition, cement of cement, gather to anticipate of the dosage of the property and dosage, in addition etc. relevant.Main prevention measure: While being to choose to use the constringency quantity smaller cement, general low hot water mire and powder ash from stove cement in the adoption, lower the dosage of cement. Two is a concrete of stem the Suo be subjected to water ash ratio of influence more big, water ash ratio more big, stem Suo more big, so in the concrete match the ratio the design should as far as possible control good water ash ratio of choose to use, the Chan add in the meantime accommodation of reduce water. Three is strict control concrete mix blend with under construction of match ratio, use of concrete water quantity absolute can't big in match ratio design give settle of use water quantity. Four is the earlier period which strengthen concrete to protect, and appropriate extension protect of concrete time. Winter construction want to be appropriate extension concrete heat preservation to overlay time, and Tu2 Shua protect to protect. Five is a constitution the accommodation is in the concrete structure of the constringency sew.2.The Su constringency crack and preventionSu constringency is the concrete is before condense, surface because of lose water quicker but creation of constringency. The Su constringency crack is general at dry heat or strong wind the weather appear, crack's much presenting in the center breadth, both ends be in the center thin and the length be different, with each other not coherent appearance. Shorter crack general long 20-30 cm, the longer crack can reach to a 2-3 m, breadth 1-5 mm. It creation of main reason is: The concrete is eventually almost having no strength or strength before the Ning very small, perhapsconcrete just eventually Ning but strength very hour, be subjected to heat or compare strong wind dint of influence, the concrete surface lose water to lead quick, result in in the capillary creation bigger negative press but make a concrete physical volume sharply constringency, but at this time the strength of concrete again can't resist its constringency, therefore creation cracked. The influence concrete Su constringency open the main factor of crack to have water ash ratio, concrete of condense time, environment temperature, wind velocity, relative humidity...etc..Main prevention measure: One is choose to use stem the Suo value smaller higher Huo sour salt of the earlier period strength or common the Huo sour brine mire. Two is strict the control water ash ratio, the Chan add to efficiently reduce water to increment the collapse of concrete fall a degree and with easy, decrease cement and water of dosage. Three is to sprinkle before building concrete, water basic level and template even to soak through. Four is in time to overlay the perhaps damp grass mat of the plastics thin film, hemp slice etc., keep concrete eventually before the Ning surface is moist, perhaps spray to protect etc. to carry on protect in the concrete surface. Five is in the heat and strong wind the weather to want to establish to hide sun and block breeze facilities, protect in time.3.Sink to sink crack and preventionThe creation which sink to sink crack is because of the structure foundation soil quality not and evenly, loose soft or return to fill soil dishonest or soak in water but result in the asymmetry sink to decline with the result that; Perhaps because of template just degree shortage, the template propped up to once be apart from big or prop up bottom loose move etc. to cause, especially at winter, the template prop up at jelly soil up, jelly the soil turn jelly empress creation asymmetry to sink to decline and cause concrete structure creation crack. This kind crack many is deep enter or pierce through sex crack, it alignment have something to do with sinking to sink a circumstance, general follow with ground perpendicular or present 30 °s-45 °Cape direction development, bigger sink to sink crack, usually have certain of wrong, crack width usually with sink to decline quantity direct proportion relation. Crack width under the influence of temperature variety smaller. The foundation aftertransform stability sink to sink crack also basic tend in stability.Main prevention measure: One is rightness loose soft soil, return to fill soil foundation a construction at the upper part structure front should carry on necessity of Hang solid with reinforce. Two is the strength that assurance template is enough and just degree, and prop up firm, and make the foundation be subjected to dint even. Three is keep concrete from sprinkle infusing the foundation in the process is soak by water. Four is time that template tore down to can't be too early, and want to notice to dismantle a mold order of sequence. Five is at jelly soil top take to establish template to notice to adopt certain of prevention measure.4.Temperature crack and preventionTemperature crack much the occurrence is in big surface or difference in temperature variety of the physical volume concrete compare the earth area of the concrete structure. Concrete after sprinkling to build, in the hardening the process, cement water turn a creation a great deal of of water turn hot, .(be the cement dosage is in the 350-550 kg/m 3, each sign square the rice concrete will release a calories of 17500-27500 kJ and make concrete internal thus the temperature rise to reach to 70 ℃or so even higher)Because the physical volume of concrete be more big, a great deal of of water turn hot accumulate at the concrete inner part but not easy send forth, cause inner part the temperature hoick, but the concrete surface spread hot more quick, so formation inside outside of bigger difference in temperature, the bigger difference in temperature result in inner part and exterior hot the degree of the bulge cold Suo dissimilarity, make concrete surface creation certain of pull should dint.When pull should dint exceed the anti- of concrete pull strength extreme limit, concrete surface meeting creation crack, this kind of crack much occurrence after the concrete under construction period.In the concrete of under construction be difference in temperature variety more big, perhaps is a concrete to be subjected to assault of cold wave etc., will cause concrete surface the temperature sharply descend, but creation constringency, surface constringency of the concrete be subjected to inner part concrete of control, creation very big of pull should dint but creation crack, this kind of crack usually just in more shallow scope ofthe concrete surface creation.The alignment of the temperature crack usually none settle regulation, big area structure the crack often maneuver interleave;The size bigger structure of the beam plank length, the crack run parallel with short side more;Thorough with pierce through sex of temperature crack general and short side direction parallelism or close parallelism, crack along long side cent the segment appear, in the center more airtight.Crack width the size be different, be subjected to temperature variety influence more obvious, winter compare breadth, summer more narrow.The concrete temperature crack that the heat inflation cause is usually in the center the thick both ends be thin, but cold Suo crack of thick thin variety not too obvious.The emergence of the this kind crack will cause the rust eclipse of reinforcing bar, the carbonization of concrete, the anti- jelly which lower concrete melt, anti- tired and anti- Shen ability etc..Main prevention measure:One is as far as possible choose to use low hot or medium hot water mire, like mineral residue cement, powder ash from stove cement...etc..Two is a decrease cement dosage, cement dosage as far as possible the control is in the 450 kg/m 3 following.Three is to lower water ash ratio, water ash of the general concrete ratio control below 0.6.Four is improvement the bone anticipate class to go together with, the Chan add powder ash from stove or efficiently reduce water etc. to come to reduce cement dosage and lower water to turn hot.Five is an improvement concrete of mix blend to process a craft, lower sprinkle of concrete to build temperature.Six is the in addition that the Chan add a have of fixed amount to reduce water and increase Su, slow Ning etc. function in the concrete, improvement the concrete mix to match a thing of mobility, protect water, lower water to turn hot, postpone hot Feng of emergence time.Seven is the heat season sprinkle to build can the adoption take to establish to hide sun plank etc. assistance measure control concrete of Wen Sheng, lower to sprinkle temperature of build the concrete.Eight is the temperature of big physical volume concrete should the dint relate to structure size, concrete structure size more big, temperature should dint more big, so want reasonable arrangement construction work preface,layering, cent the piece sprinkle to build, for the convenience of in spread hot, let up control.Nine is at great inner part constitution of the physical volume concrete cool off piping, cold water perhaps cold air cool off, let up concrete of inside outside difference in temperature.Ten is the supervision which strengthen concrete temperature, adopt to cool off in time, protection measure.11 is to reserve temperature constringency to sew.12 is to let up to control, sprinkle proper before building concrete in the Ji rock and old concrete top build a 5 mm or so sand mat a layer or usage asphalt etc. material Tu2 Shua.13 is to strengthen concrete to protect, the concrete after sprinkle build use moist grass Lian in time, hemp slice's etc. overlay, and attention sprinkle water to protect, appropriate extension protect time, assurance the concrete surface be slow-moving cool off.At the cold season, concrete surface should constitution heat preservation measure, in order to prevent cold wave assault.14 is the allocation be a little amount in the concrete of reinforcing bar perhaps add fiber material concrete of temperature crack control at certain of scope inside.5.Crack and prevention that the chemical reaction causeAlkali bone's anticipating the crack that reaction crack and reinforcing bar rust eclipse cause is the most familiar in the reinforced concrete structure of because of chemical reaction but cause of crack.The concrete blend a future reunion creation some alkalescence ion, these ion with some activity the bone anticipate creation chemical reaction and absorb surroundings environment in of water but the physical volume enlarge, make concrete crisp loose, inflation open crack.In this kind of crack general emergence concrete structure usage period, once appear very difficult remediable, so should at under construction adopt valid the measure carry on prevention.Main of prevention measure:While being to choose to anticipate with the alkali activity small freestone bone.Two is the in addition which choose to use low lye mire with low alkali or have no alkali.Three is the Chan which choose to use accommodation with anticipate to repress an alkali bone to anticipate reaction.Because the concrete sprinkle to build, flap Dao bad perhaps is a reinforcingbar protection layer thinner, the harmful material get into concrete to make reinforcing bar creation rust eclipse, the reinforcing bar physical volume of the rust eclipse inflation, cause concrete bulge crack, the crack of this kind type much is a crack lengthways, follow the position of reinforcing bar ually of prevent measure from have:One is assurance reinforcing bar protection the thickness of the layer.Two is a concrete class to go together with to want good.Three is a concrete to sprinkle to note and flap Dao airtight solid.Four is a reinforcing bar surface layer Tu2 Shua antisepsis coating.Crack processingThe emergence of the crack not only would influence structure of whole with just degree, return will cause the rust eclipse of reinforcing bar, acceleration concrete of carbonization, lower durable and anti- of concrete tired, anti- Shen ability.Therefore according to the property of crack and concrete circumstance we want differentiation to treat, in time processing, with assurance building of safety usage.The repair measure of the concrete crack is main to have the following some method:Surface repair method, infuse syrup, the Qian sew method, the structure reinforce a method, concrete displacement method, electricity chemistry protection method and imitate to living from heal method.Surface repair the method be a kind of simple, familiar of repair method, it main be applicable to stability and to structure loading the ability don't have the surface crack of influence and deep enter crack of processing.The processing measure that is usually is a surface in crack daubery cement syrup, the wreath oxygen gum mire or at concrete surface Tu2 Shua paint, asphalt etc. antisepsis material, at protection of in the meantime for keeping concrete from continue under the influence of various function to open crack, usually can adoption the surface in crack glue to stick glass fiber cloth etc. measure.1, infuse syrup, the Qian sew methodInfuse a syrup method main the concrete crack been applicable to haveinfluence or have already defend Shen request to the structure whole of repair, it is make use of pressure equipments gum knot the material press into the crack of concrete, gum knot the material harden behind and concrete formation one be whole, thus reinforce of purpose.The in common use gum knot material has the cement the syrup, epoxy, A Ji C Xi sour ester and gather ammonia ester to equalize to learn material.The Qian sew a method is that the crack be a kind of most in common use method in, it usually is follow the crack dig slot, the Qian fill Su in the slot or rigid water material with attain closing crack of purpose.The in common use Su material has PVC gum mire, plastics ointment, the D Ji rubber etc.;In common use rigid water material is the polymer cement sand syrup.2, the structure reinforce a methodWhen the crack influence arrive concrete structure of function, will consideration adopt to reinforce a method to carry on processing to the concrete structure.The structure reinforce medium in common use main have the following a few method:The piece of enlargement concrete structure in every aspect accumulate, outside the Cape department of the Gou piece pack type steel, adoption prepare should the dint method reinforce, glue to stick steel plate to reinforce, increase to establish fulcrum to reinforce and jet the concrete compensation reinforce.3, concrete displacement methodConcrete displacement method is processing severity damage concrete of a kind of valid method, this method be first will damage of the concrete pick and get rid of, then again displacement go into new of concrete or other material.The in common use displacement material have:Common concrete or the cement sand syrup, polymer or change sex polymer concrete or sand syrup.4, the electricity chemistry protection methodThe electricity chemistry antisepsis is to make use of infliction electric field in lie the quality of electricity chemical effect, change concrete or reinforced concrete the environment appearance of the place, the bluntness turn reinforcing bar to attainthe purpose of antisepsis.Cathode protection method, chlorine salt's withdrawing a method, alkalescence to recover a method is a chemistry protection method in three kinds of in common use but valid method.The advantage of this kind of method is a protection method under the influence of environment factor smaller, apply reinforcing bar, concrete of long-term antisepsis, since can used for crack structure already can also used for new set up structure.5, imitate to living from legal moreImitate to living from heal the method be a kind of new crack treatment, its mimicry living creature organization secrete a certain material towards suffering wound part auto, but make the wound part heal of function, join some and special composition(such as contain to glue knot of the liquid Xin fiber or capsule) in the concrete of the tradition the composition, at concrete inner part formation the intelligence type imitate to living from heal nerve network system, be the concrete appear crack secrete a parts of liquid Xin fiber can make the crack re- heal.ConclusionThe crack is widespread in the concrete structure existence of a kind of phenomenon, it of emergence not only will lower the anti- Shen of building ability, influence building of usage function, and will cause the rust eclipse of reinforcing bar, the carbonization of concrete, lower the durable of material, influence building of loading ability, so want to carry on to the concrete crack earnest research, differentiation treat, adoption reasonable of the method carry on processing, and at under construction adopt various valid of prevention measure to prevention crack of emergence and development, assurance building and Gou piece safety, stability work.From《CANADIAN JOURNAL OF CIVIL ENGINEERING》中文原文：建筑施工混凝土裂缝的预防与处理混凝土的裂缝问题是一个普遍存在而又难于解决的工程实际问题，本文对混凝土工程中常见的一些裂缝问题进行了探讨分析，并针对具体情况提出了一些预防、处理措施。
土木工程专业英语带译文
Chapter 6
If a material with high strength in tension, such as steel, is placed in concrete, then the composite material, reinforced concrete, resists not only compression but also bending and other direct tensile actions. A reinforced concrete section where the concrete resists the compression and steel resists the tension can be made into almost any shape and size for the construction industry.
6. —We shall finish the civil work by the end of the year. 在年底前我们将完成土建工作。 —Cement steel and timber are the most important construction materials used in civil engineering. 水泥、钢材和木材是土建工程中最重要的建筑材料。 7. These are the anchor bolts (rivets, unfinished bolts, high-strength structural bolts) for the structure. 这是用于结构的锚定螺栓（铆钉、粗制螺栓、高强度结构用螺栓）。
Chapter 6
Chapter 6 Reinforced Concrete
土木工程专业外文翻译--土木工程
外文原文：Civil EngineeringCivil engineering is the planning, design, construction, and management of the built environment. This environment includes all structures built according to scientific principles, from irrigation and drainage systems to rocket launching facilities.Civil engineers build roads, bridges, tunnels, dams, harbors, power plants, water and sewage systems, hospitals, schools, mass transit, and other public facilities essential to modern society and large population concentrations. They also build privately owned facilities such as airport, railroads, pipelines, skyscrapers, and other large structures designed for industrial, commercial, or residential use. In addition, civil engineers plan, design, and build complete cities and towns, and more recently have been planning and designing space platforms to self-contained communities.The word civil derives from the Latin for citizen. In 1782, Englishman John Seaton used the term to differentiate his nonmilitary engineering work from that of the military engineers who predominated at the time. Since then, the term civil engineer has often been used to refer to engineers who build public facilities, although the field is much broader.Scope Because it is so broad, civil engineering is subdivided into a number of technical specialties. Depending on the type of project, the skills pf many kinds of civil engineer specialties may be needed. When a project begins, the site is surveyed and mapped by civil engineers who experiment to determine if the earth can bear the weight of project. Environmental specialists study the project’s impact on the local area, the potential for air and groundwater pollution, the project’s impact on local animal and plant life, and how the project can be designed to meet government requirements aimed at protecting the environment. Transportation specialists determine what kind of facilities are needed to ease the burden on local roads and other transportation networks that will result from the completed project. Meanwhile, structural specialists raise preliminary data to make detailed designs, plans, and specifications for the project. Supervising and coordinating the work of these civil engineer specialists, from beginning to end of the project, are the construction management specialists. Based on information supplied by the other specialists, construction management civil engineers estimate quantitiesand costs of materials and subcontractors, and perform other supervisory work to ensure the project is completed on time and as specified.Many civil engineers, among them the top people in the field, work in design. As we have seen, civil engineers work on many different kinds of structures, so it is normal practice for an engineer to specialize in just one kind. In designing buildings, engineers often work as consultants to architectural or construction firms. Dams, bridges, water supply systems, and other large projects ordinarily employ several engineers whose work is coordinated by a system engineer who is in charge of the entire project. In many cases, engineers from other disciplines are involved. In a dam project, for example, electrical and mechanical engineers work on the design of the powerhouse and its equipment. In other cases, civil engineers are assigned to work on a project in another field; in the space program, for instance, civil engineers were necessary in the design and construction of such structures as launching pads and rocket storage facilities.Throughout any given project, civil engineers make extensive use of computers. Computes are used to design the project’s various elements (computer-aided design, or CAD) and to manger it. Computers are a necessity for the modern civil engineer because they permit the engineer to efficiently handle the large quantities of data needed in determining the best way to construct a project.Structural engineering In this specialty, civil engineers plan and design structures of all types, including bridges dams, power plants, supports for equipment, special structures for offshore projects, the United States space program, transmission towers, giant astronomical and radio telescopes, and many other kinds of projects.Using computers, structural engineers determine the forces a structure must resist, its own weight, wind and hurricane forces temperature changes that expand or contract construction materials, and earthquakes. They also determine the combination of appropriate materials: steel, concrete, plastic, stone, asphalt, brick, aluminum, or other construction materials.Water resources engineering Civil engineers in this specialty deal with all aspects of the physical control of water. Their projects help prevent floods, supply water for cities and for irrigation, manage and control rivers and water runoff, and maintain beaches and other waterfront facilities. In addition, they design and maintain harbors, canals, and locks, build huge hydroelectric dams and smaller dams and water impoundments of all kinds, help design offshorestructures, and determine the location of structures affecting navigation.Geotechnical engineering Civil engineers who specialize in this filed analyze the properties of soils and rocks that support structures and affect structural behavior. They evaluate and work to minimize the potential settlement of buildings and other structures that stems from the pressure of their weight on the earth. These engineers also evaluate and determine how to strengthen the stability of slopes and how to protect structures against earthquakes and the effects of groundwater.Environmental engineering In this branch of engineering, civil engineers design, build, and supervise systems to provide safe drinking water and to prevent and control pollution of water supplies, both on the surface and underground. They also design, build, and supervise projects to control or eliminate pollution of the land and air. These engineers build water and wastewaters treatment plants, and design air scrubbers and other devices to minimize or eliminate air pollution caused by industrial processes, incineration, or other smoke-producing activities. They also work to control toxic and hazardous wastes through the construction of special dump sites or the neutralizing of toxic and hazardous substances. In addition the engineers design and manage sanitary landfills to prevent pollution of surrounding land.Transportation engineering Civil engineers working in this specialty build facilities to ensure safe and efficient movement of both people and goods. They specialize in designing and maintaining all types of transportation facilities, highways and streets, mass transit systems, railroads and airfields ports and harbors. Transportation engineers apply technological knowledge as well as consideration of the economic, political, and social factors in designing each project. They work closely with urban planners since the quality of the community is directly related to the quality of the transportation system.Pipeline engineering In this branch of civil engineering, engineers build pipelines and related facilities, which transport liquids, gases, or solids ranging from coal slurries (mixed coal and water) and semi liquids wastes, to water, oil and various types pf highly combustible and noncombustible gases. The engineers determine pipeline design, the economic and environmental impact of a project on regions it must traverse, the type pf materials to be used-steel, concrete, plastic, or combinations of various materials, installation techniques, methods for testing pipeline strength, and controls for maintaining proper pressure and rate of flow of materials being transported. When hazardous materials are being carried, safety is a major consideration as well.Construction engineering Civil engineers in this field oversee the construction of a project from beginning to end. Sometimes called project engineers, they apply both technical and managerial skills, including knowledge of construction methods, planning, organizing, financing, and operating construction projects. They coordinate the activities of virtually everyone engaged in the work: the surveyors, workers who lay out and construct the temporary roads and ramps, excavate for the foundation, build the forms and pour the concrete; and workers who build the steel frame-work. These engineers also make regular progress reports to the owners of the structure.Construction is a complicated process on almost all engineering projects. It involves scheduling the work and utilizing the equipment and the materials so that coats are kept as low as possible. Safety factor must also be taken into account, since construction can be very dangerous. Many civil engineers therefore specialize in the construction phase.Community and urban planning Those engaged in this area of civil engineering may plan and develop communities within a city, or entire cities. Such planning involves far more than engineering considerations; environmental, social, and economic factors in the use and development of land and natural resources are also key elements. They evaluate the kinds of facilities needed, including streets and highways, public transportation systems, airports, and recreational and other facilities to ensure social and economic as well as environmental well-being.Photogrammetry, surveying, and mapping The civil engineers in this specialty precisely measure the Earth’s surface to obtain reliable information for locating and designing engineering projects. This practice often involves high-technology methods such as satellite and aerial surveying, and computer processing of photographic imagery. Radio signals from satellites, scanned by laser and sonic beams, are converted to maps to provide very accurate measurements for boring tunnels, building highways and dams, plotting flood control and irrigation projects, locating subsurface geologic formations that may affect a construction project and a host of other building uses.Other specialties Three additional civil engineering specialties that are not entirely within the scope of civil engineering teaching.Engineering research Research is one of the most important aspects of scientific and engineering practice. A researcher usually works as a member of a team with other scientists and engineers. He or she is often employed in alaboratory that financed by government or industry. Areas of research connected with civil engineering include soil mechanics and soil stabilization techniques, and also the development and testing of new structural materials.Engineering management Many civil engineers choose careers that eventually lead to management. Others are also to start their careers in management positions. The civil engineer manager combines technical knowledge with an ability to organize and coordinate worker power, materials, machinery, and money. These engineers may work in government municipal, county, state, or federal; in the U.S.Army Corps of Engineers as military or civilian management engineers; or in semiautonomous regional or city authorities or similar organization. They may also manage private engineering firms ranging in size from a few employees to hundreds.Engineering teaching The civil engineer who chooses a teaching career usually teaches both graduate and undergraduate students in technical specialties. Many teaching civil engineers engage in basic research that eventually leads to technical innovations in construction materials and methods. Many also serve as consultants on engineering projects, or on technical boards and commissions associated with major projects.中文译文：土木工程土木工程是指对建成环境的规划、设计、建造、管理等一系列活动。
土木工程 外文翻译 外文文献 英文文献
一、外文原文Talling building and Steel construction Although there have been many advancements in building construction technology in general. Spectacular archievements have been made in the design and construction of ultrahigh-rise buildings.The early development of high-rise buildings began with structural steel framing.Reinforced concrete and stressed-skin tube systems have since been economically and competitively used in a number of structures for both residential and commercial purposes.The high-rise buildings ranging from 50 to 110 stories that are being built all over the United States are the result of innovations and development of new structual systems.Greater height entails increased column and beam sizes to make buildings more rigid so that under wind load they will not sway beyond an acceptable limit.Excessive lateral sway may cause serious recurring damage to partitions,ceilings.and other architectural details. In addition,excessive sway may cause discomfort to the occupants of the building because their perception of such motion.Structural systems of reinforced concrete,as well as steel,take full advantage of inherent potential stiffness of the total building and therefore require additional stiffening to limit the sway.In a steel structure,for example,the economy can be defined in terms of the total average quantity of steel per square foot of floor area of the building.Curve A in Fig .1 represents the average unit weight of a conventional frame with increasing numbers of stories. Curve B represents the average steel weight if the frame is protected from all lateral loads. The gap between the upper boundary and the lower boundary represents the premium for height for the traditional column-and-beam frame.Structural engineers have developed structural systems with a view to eliminating this premium.Systems in steel. Tall buildings in steel developed as a result ofseveral types of structural innovations. The innovations have been applied to the construction of both office and apartment buildings.Frame with rigid belt trusses. In order to tie the exterior columns of a frame structure to the interior vertical trusses,a system of rigid belt trusses at mid-height and at the top of the building may be used. A good example of this system is the First Wisconsin Bank Building(1974) in Milwaukee.Framed tube. The maximum efficiency of the total structure of a tall building, for both strength and stiffness,to resist wind load can be achieved only if all column element can be connected to each other in such a way that the entire building acts as a hollow tube or rigid box in projecting out of the ground. This particular structural system was probably used for the first time in the 43-story reinforced concrete DeWitt Chestnut Apartment Building in Chicago. The most significant use of this system is in the twin structural steel towers of the 110-story World Trade Center building in New York Column-diagonal truss tube. The exterior columns of a building can be spaced reasonably far apart and yet be made to work together as a tube by connecting them with diagonal members interesting at the centre line of the columns and beams. This simple yet extremely efficient system was used for the first time on the John Hancock Centre in Chicago, using as much steel as is normally needed for a traditional 40-story building.Bundled tube. With the continuing need for larger and taller buildings, the framed tube or the column-diagonal truss tube may be used in a bundled form to create larger tube envelopes while maintaining high efficiency. The 110-story Sears Roebuck Headquarters Building in Chicago has nine tube, bundled at the base of the building in three rows. Some of these individual tubes terminate at different heights of the building, demonstrating the unlimited architectural possibilities of this latest structural concept. The Sears tower, at a height of 1450 ft(442m), is the world’s tallest building.Stressed-skin tube system. The tube structural system was developed for improving the resistance to lateral forces (wind and earthquake) and thecontrol of drift (lateral building movement ) in high-rise building. The stressed-skin tube takes the tube system a step further. The development of the stressed-skin tube utilizes the façade of the building as a structural element which acts with the framed tube, thus providing an efficient way of resisting lateral loads in high-rise buildings, and resulting in cost-effective column-free interior space with a high ratio of net to gross floor area.Because of the contribution of the stressed-skin façade, the framed members of the tube require less mass, and are thus lighter and less expensive. All the typical columns and spandrel beams are standard rolled shapes,minimizing the use and cost of special built-up members. The depth requirement for the perimeter spandrel beams is also reduced, and the need for upset beams above floors, which would encroach on valuable space, is minimized. The structural system has been used on the 54-story One Mellon Bank Center in Pittburgh.Systems in concrete. While tall buildings constructed of steel had an early start, development of tall buildings of reinforced concrete progressed at a fast enough rate to provide a competitive chanllenge to structural steel systems for both office and apartment buildings.Framed tube. As discussed above, the first framed tube concept for tall buildings was used for the 43-story DeWitt Chestnut Apartment Building. In this building ,exterior columns were spaced at 5.5ft (1.68m) centers, and interior columns were used as needed to support the 8-in . -thick (20-m) flat-plate concrete slabs.Tube in tube. Another system in reinforced concrete for office buildings combines the traditional shear wall construction with an exterior framed tube. The system consists of an outer framed tube of very closely spaced columns and an interior rigid shear wall tube enclosing the central service area. The system known as the tube-in-tube system , made it possible to design the world’s present tallest (714ft or 218m)lightweight concrete bu ilding( the 52-story One Shell Plaza Building in Houston) for the unit price of a traditional shear wall structure of only 35 stories.Systems combining both concrete and steel have also been developed, an examle of which is the composite system developed by skidmore, Owings &Merril in which an exterior closely spaced framed tube in concrete envelops an interior steel framing, thereby combining the advantages of both reinforced concrete and structural steel systems. The 52-story One Shell Square Building in New Orleans is based on this system.Steel construction refers to a broad range of building construction in which steel plays the leading role. Most steel construction consists of large-scale buildings or engineering works, with the steel generally in the form of beams, girders, bars, plates, and other members shaped through the hot-rolled process. Despite the increased use of other materials, steel construction remained a major outlet for the steel industries of the U.S, U.K, U.S.S.R, Japan, West German, France, and other steel producers in the 1970s.二、原文翻译高层结构与钢结构近年来，尽管一般的建筑结构设计取得了很大的进步，但是取得显著成绩的还要属超高层建筑结构设计。
土木工程--外文文献翻译
土木工程--外文文献翻译-CAL-FENGHAI.-(YICAI)-Company One1学院：专业：土木工程姓名：学号：外文出处： Structural Systems to resist (用外文写)Lateral loads附件： 1.外文资料翻译译文；2.外文原文。
附件1：外文资料翻译译文抗侧向荷载的结构体系常用的结构体系若已测出荷载量达数千万磅重，那么在高层建筑设计中就没有多少可以进行极其复杂的构思余地了。
确实，较好的高层建筑普遍具有构思简单、表现明晰的特点。
这并不是说没有进行宏观构思的余地。
实际上，正是因为有了这种宏观的构思，新奇的高层建筑体系才得以发展，可能更重要的是：几年以前才出现的一些新概念在今天的技术中已经变得平常了。
如果忽略一些与建筑材料密切相关的概念不谈，高层建筑里最为常用的结构体系便可分为如下几类：1.抗弯矩框架。
2.支撑框架，包括偏心支撑框架。
3.剪力墙，包括钢板剪力墙。
4.筒中框架。
5.筒中筒结构。
6.核心交互结构。
7. 框格体系或束筒体系。
特别是由于最近趋向于更复杂的建筑形式，同时也需要增加刚度以抵抗几力和地震力，大多数高层建筑都具有由框架、支撑构架、剪力墙和相关体系相结合而构成的体系。
而且，就较高的建筑物而言，大多数都是由交互式构件组成三维陈列。
将这些构件结合起来的方法正是高层建筑设计方法的本质。
其结合方式需要在考虑环境、功能和费用后再发展，以便提供促使建筑发展达到新高度的有效结构。
这并不是说富于想象力的结构设计就能够创造出伟大建筑。
正相反，有许多例优美的建筑仅得到结构工程师适当的支持就被创造出来了，然而，如果没有天赋甚厚的建筑师的创造力的指导，那么，得以发展的就只能是好的结构，并非是伟大的建筑。
无论如何，要想创造出高层建筑真正非凡的设计，两者都需要最好的。
虽然在文献中通常可以见到有关这七种体系的全面性讨论，但是在这里还值得进一步讨论。
设计方法的本质贯穿于整个讨论。
土木工程 专业外语词汇大全中英翻译
土木工程专业外语词汇大全中英翻译1. 综合类大地工程geotechnical engineering1. 综合类反分析法back analysis method1. 综合类基础工程foundation engineering1. 综合类临界状态土力学critical state soil mechanics1. 综合类数值岩土力学numerical geomechanics1. 综合类土soil, earth1. 综合类土动力学soil dynamics1. 综合类土力学soil mechanics1. 综合类岩土工程geotechnical engineering1. 综合类应力路径stress path1. 综合类应力路径法stress path method2. 工程地质及勘察变质岩metamorphic rock2. 工程地质及勘察标准冻深standard frost penetration2. 工程地质及勘察冰川沉积glacial deposit2. 工程地质及勘察冰积层（台）glacial deposit2. 工程地质及勘察残积土eluvial soil, residual soil2. 工程地质及勘察层理beding2. 工程地质及勘察长石feldspar2. 工程地质及勘察沉积岩sedimentary rock2. 工程地质及勘察承压水confined water2. 工程地质及勘察次生矿物secondary mineral2. 工程地质及勘察地质年代geological age2. 工程地质及勘察地质图geological map2. 工程地质及勘察地下水groundwater2. 工程地质及勘察断层fault2. 工程地质及勘察断裂构造fracture structure2. 工程地质及勘察工程地质勘察engineering geological exploration 2. 工程地质及勘察海积层（台）marine deposit2. 工程地质及勘察海相沉积marine deposit2. 工程地质及勘察花岗岩granite2. 工程地质及勘察滑坡landslide2. 工程地质及勘察化石fossil2. 工程地质及勘察化学沉积岩chemical sedimentary rock2. 工程地质及勘察阶地terrace2. 工程地质及勘察节理joint2. 工程地质及勘察解理cleavage2. 工程地质及勘察喀斯特karst2. 工程地质及勘察矿物硬度hardness of minerals2. 工程地质及勘察砾岩conglomerate2. 工程地质及勘察流滑flow slide2. 工程地质及勘察陆相沉积continental sedimentation2. 工程地质及勘察泥石流mud flow, debris flow2. 工程地质及勘察年粘土矿物clay minerals2. 工程地质及勘察凝灰岩tuff2. 工程地质及勘察牛轭湖ox-bow lake2. 工程地质及勘察浅成岩hypabyssal rock2. 工程地质及勘察潜水ground water2. 工程地质及勘察侵入岩intrusive rock2. 工程地质及勘察取土器geotome2. 工程地质及勘察砂岩sandstone2. 工程地质及勘察砂嘴spit, sand spit2. 工程地质及勘察山岩压力rock pressure2. 工程地质及勘察深成岩plutionic rock2. 工程地质及勘察石灰岩limestone2. 工程地质及勘察石英quartz2. 工程地质及勘察松散堆积物rickle2. 工程地质及勘察围限地下水（台）confined ground water 2. 工程地质及勘察泻湖lagoon2. 工程地质及勘察岩爆rock burst2. 工程地质及勘察岩层产状attitude of rock2. 工程地质及勘察岩浆岩magmatic rock, igneous rock2. 工程地质及勘察岩脉dike, dgke2. 工程地质及勘察岩石风化程度degree of rock weathering 2. 工程地质及勘察岩石构造structure of rock2. 工程地质及勘察岩石结构texture of rock2. 工程地质及勘察岩体rock mass2. 工程地质及勘察页岩shale2. 工程地质及勘察原生矿物primary mineral2. 工程地质及勘察云母mica2. 工程地质及勘察造岩矿物rock-forming mineral2. 工程地质及勘察褶皱fold, folding2. 工程地质及勘察钻孔柱状图bore hole columnar section3. 土的分类饱和土saturated soil3. 土的分类超固结土overconsolidated soil3. 土的分类冲填土dredger fill3. 土的分类充重塑土3. 土的分类冻土frozen soil, tjaele3. 土的分类非饱和土unsaturated soil3. 土的分类分散性土dispersive soil3. 土的分类粉土silt, mo3. 土的分类粉质粘土silty clay3. 土的分类高岭石kaolinite3. 土的分类过压密土（台）overconsolidated soil3. 土的分类红粘土red clay, adamic earth3. 土的分类黄土loess, huangtu(China)3. 土的分类蒙脱石montmorillonite3. 土的分类泥炭peat, bog muck3. 土的分类年粘土clay3. 土的分类年粘性土cohesive soil, clayey soil3. 土的分类膨胀土expansive soil, swelling soil3. 土的分类欠固结粘土underconsolidated soil3. 土的分类区域性土zonal soil3. 土的分类人工填土fill, artificial soil3. 土的分类软粘土soft clay, mildclay, mickle3. 土的分类砂土sand3. 土的分类湿陷性黄土collapsible loess, slumping loess3. 土的分类素填土plain fill3. 土的分类塑性图plasticity chart3. 土的分类碎石土stone, break stone, broken stone, channery, chat, crushed stone, deritus 3. 土的分类未压密土（台）underconsolidated clay3. 土的分类无粘性土cohesionless soil, frictional soil, non-cohesive soil3. 土的分类岩石rock3. 土的分类伊利土illite3. 土的分类有机质土organic soil3. 土的分类淤泥muck, gyttja, mire, slush3. 土的分类淤泥质土mucky soil3. 土的分类原状土undisturbed soil3. 土的分类杂填土miscellaneous fill3. 土的分类正常固结土normally consolidated soil3. 土的分类正常压密土（台）normally consolidated soil3. 土的分类自重湿陷性黄土self weight collapse loess4. 土的物理性质阿太堡界限Atterberg limits4. 土的物理性质饱和度degree of saturation4. 土的物理性质饱和密度saturated density4. 土的物理性质饱和重度saturated unit weight4. 土的物理性质比重specific gravity4. 土的物理性质稠度consistency4. 土的物理性质不均匀系数coefficient of uniformity, uniformity coefficient4. 土的物理性质触变thixotropy4. 土的物理性质单粒结构single-grained structure4. 土的物理性质蜂窝结构honeycomb structure4. 土的物理性质干重度dry unit weight4. 土的物理性质干密度dry density4. 土的物理性质塑性指数plasticity index4. 土的物理性质含水量water content, moisture content4. 土的物理性质活性指数4. 土的物理性质级配gradation, grading4. 土的物理性质结合水bound water, combined water, held water4. 土的物理性质界限含水量Atterberg limits4. 土的物理性质颗粒级配particle size distribution of soils, mechanical composition of soil 4. 土的物理性质可塑性plasticity4. 土的物理性质孔隙比void ratio4. 土的物理性质孔隙率porosity4. 土的物理性质粒度granularity, grainness, grainage4. 土的物理性质粒组fraction, size fraction4. 土的物理性质毛细管水capillary water4. 土的物理性质密度density4. 土的物理性质密实度compactionness4. 土的物理性质年粘性土的灵敏度sensitivity of cohesive soil4. 土的物理性质平均粒径mean diameter, average grain diameter4. 土的物理性质曲率系数coefficient of curvature4. 土的物理性质三相图block diagram, skeletal diagram, three phase diagram4. 土的物理性质三相土tri-phase soil4. 土的物理性质湿陷起始应力initial collapse pressure4. 土的物理性质湿陷系数coefficient of collapsibility4. 土的物理性质缩限shrinkage limit4. 土的物理性质土的构造soil texture4. 土的物理性质土的结构soil structure4. 土的物理性质土粒相对密度specific density of solid particles4. 土的物理性质土中气air in soil4. 土的物理性质土中水water in soil4. 土的物理性质团粒aggregate, cumularpharolith4. 土的物理性质限定粒径constrained diameter4. 土的物理性质相对密度relative density, density index4. 土的物理性质相对压密度relative compaction, compacting factor, percent compaction, coefficient of compaction4. 土的物理性质絮状结构flocculent structure4. 土的物理性质压密系数coefficient of consolidation4. 土的物理性质压缩性compressibility4. 土的物理性质液限liquid limit4. 土的物理性质液性指数liquidity index4. 土的物理性质游离水（台）free water4. 土的物理性质有效粒径effective diameter, effective grain size, effective size4. 土的物理性质有效密度effective density4. 土的物理性质有效重度effective unit weight4. 土的物理性质重力密度unit weight4. 土的物理性质自由水free water, gravitational water, groundwater, phreatic water4. 土的物理性质组构fabric4. 土的物理性质最大干密度maximum dry density4. 土的物理性质最优含水量optimum water content5. 渗透性和渗流达西定律Darcy s law5. 渗透性和渗流管涌piping5. 渗透性和渗流浸润线phreatic line5. 渗透性和渗流临界水力梯度critical hydraulic gradient5. 渗透性和渗流流函数flow function5. 渗透性和渗流流土flowing soil5. 渗透性和渗流流网flow net5. 渗透性和渗流砂沸sand boiling5. 渗透性和渗流渗流seepage5. 渗透性和渗流渗流量seepage discharge5. 渗透性和渗流渗流速度seepage velocity5. 渗透性和渗流渗透力seepage force5. 渗透性和渗流渗透破坏seepage failure5. 渗透性和渗流渗透系数coefficient of permeability5. 渗透性和渗流渗透性permeability5. 渗透性和渗流势函数potential function5. 渗透性和渗流水力梯度hydraulic gradient6. 地基应力和变形变形deformation6. 地基应力和变形变形模量modulus of deformation6. 地基应力和变形泊松比Poisson s ratio6. 地基应力和变形布西涅斯克解Boussinnesq s solution6. 地基应力和变形残余变形residual deformation6. 地基应力和变形残余孔隙水压力residual pore water pressure6. 地基应力和变形超静孔隙水压力excess pore water pressure6. 地基应力和变形沉降settlement6. 地基应力和变形沉降比settlement ratio6. 地基应力和变形次固结沉降secondary consolidation settlement6. 地基应力和变形次固结系数coefficient of secondary consolidation6. 地基应力和变形地基沉降的弹性力学公式elastic formula for settlement calculation 6. 地基应力和变形分层总和法layerwise summation method6. 地基应力和变形负孔隙水压力negative pore water pressure6. 地基应力和变形附加应力superimposed stress6. 地基应力和变形割线模量secant modulus6. 地基应力和变形固结沉降consolidation settlement6. 地基应力和变形规范沉降计算法settlement calculation by specification6. 地基应力和变形回弹变形rebound deformation6. 地基应力和变形回弹模量modulus of resilience6. 地基应力和变形回弹系数coefficient of resilience6. 地基应力和变形回弹指数swelling index6. 地基应力和变形建筑物的地基变形允许值allowable settlement of building6. 地基应力和变形剪胀dilatation6. 地基应力和变形角点法corner-points method6. 地基应力和变形孔隙气压力pore air pressure6. 地基应力和变形孔隙水压力pore water pressure6. 地基应力和变形孔隙压力系数Apore pressure parameter A6. 地基应力和变形孔隙压力系数Bpore pressure parameter B6. 地基应力和变形明德林解Mindlin s solution6. 地基应力和变形纽马克感应图Newmark chart6. 地基应力和变形切线模量tangent modulus6. 地基应力和变形蠕变creep6. 地基应力和变形三向变形条件下的固结沉降three-dimensional consolidation settlement 6. 地基应力和变形瞬时沉降immediate settlement6. 地基应力和变形塑性变形plastic deformation6. 地基应力和变形谈弹性变形elastic deformation6. 地基应力和变形谈弹性模量elastic modulus6. 地基应力和变形谈弹性平衡状态state of elastic equilibrium6. 地基应力和变形体积变形模量volumetric deformation modulus6. 地基应力和变形先期固结压力preconsolidation pressure6. 地基应力和变形压缩层6. 地基应力和变形压缩模量modulus of compressibility6. 地基应力和变形压缩系数coefficient of compressibility6. 地基应力和变形压缩性compressibility6. 地基应力和变形压缩指数compression index6. 地基应力和变形有效应力effective stress6. 地基应力和变形自重应力self-weight stress6. 地基应力和变形总应力total stress approach of shear strength6. 地基应力和变形最终沉降final settlement7. 固结巴隆固结理论Barron s consolidation theory7. 固结比奥固结理论Biot s consolidation theory7. 固结超固结比over-consolidation ratio7. 固结超静孔隙水压力excess pore water pressure7. 固结次固结secondary consolidation7. 固结次压缩（台）secondary consolidatin7. 固结单向度压密（台）one-dimensional consolidation7. 固结多维固结multi-dimensional consolidation7. 固结固结consolidation7. 固结固结度degree of consolidation7. 固结固结理论theory of consolidation7. 固结固结曲线consolidation curve7. 固结固结速率rate of consolidation7. 固结固结系数coefficient of consolidation7. 固结固结压力consolidation pressure7. 固结回弹曲线rebound curve7. 固结井径比drain spacing ratio7. 固结井阻well resistance7. 固结曼代尔－克雷尔效应Mandel-Cryer effect7. 固结潜变（台）creep7. 固结砂井sand drain7. 固结砂井地基平均固结度average degree of consolidation of sand-drained ground7. 固结时间对数拟合法logrithm of time fitting method7. 固结时间因子time factor7. 固结太沙基固结理论Terzaghi s consolidation theory7. 固结太沙基－伦杜列克扩散方程Terzaghi-Rendulic diffusion equation7. 固结先期固结压力preconsolidation pressure7. 固结压密（台）consolidation7. 固结压密度（台）degree of consolidation7. 固结压缩曲线cpmpression curve7. 固结一维固结one dimensional consolidation7. 固结有效应力原理principle of effective stress7. 固结预压密压力（台）preconsolidation pressure7. 固结原始压缩曲线virgin compression curve7. 固结再压缩曲线recompression curve7. 固结主固结primary consolidation7. 固结主压密（台）primary consolidation7. 固结准固结压力pseudo-consolidation pressure7. 固结K0固结consolidation under K0 condition8. 抗剪强度安息角（台）angle of repose8. 抗剪强度不排水抗剪强度undrained shear strength8. 抗剪强度残余内摩擦角residual angle of internal friction8. 抗剪强度残余强度residual strength8. 抗剪强度长期强度long-term strength8. 抗剪强度单轴抗拉强度uniaxial tension test8. 抗剪强度动强度dynamic strength of soils8. 抗剪强度峰值强度peak strength8. 抗剪强度伏斯列夫参数Hvorslev parameter8. 抗剪强度剪切应变速率shear strain rate8. 抗剪强度抗剪强度shear strength8. 抗剪强度抗剪强度参数shear strength parameter8. 抗剪强度抗剪强度有效应力法effective stress approach of shear strength 8. 抗剪强度抗剪强度总应力法total stress approach of shear strength8. 抗剪强度库仑方程Coulomb s equation8. 抗剪强度摩尔包线Mohr s envelope8. 抗剪强度摩尔－库仑理论Mohr-Coulomb theory8. 抗剪强度内摩擦角angle of internal friction8. 抗剪强度年粘聚力cohesion8. 抗剪强度破裂角angle of rupture8. 抗剪强度破坏准则failure criterion8. 抗剪强度十字板抗剪强度vane strength8. 抗剪强度无侧限抗压强度unconfined compression strength8. 抗剪强度有效内摩擦角effective angle of internal friction8. 抗剪强度有效粘聚力effective cohesion intercept8. 抗剪强度有效应力破坏包线effective stress failure envelope8. 抗剪强度有效应力强度参数effective stress strength parameter8. 抗剪强度有效应力原理principle of effective stress8. 抗剪强度真内摩擦角true angle internal friction8. 抗剪强度真粘聚力true cohesion8. 抗剪强度总应力破坏包线total stress failure envelope8. 抗剪强度总应力强度参数total stress strength parameter9. 本构模型本构模型constitutive model9. 本构模型边界面模型boundary surface model9. 本构模型层向各向同性体模型cross anisotropic model9. 本构模型超弹性模型hyperelastic model9. 本构模型德鲁克－普拉格准则Drucker-Prager criterion9. 本构模型邓肯－张模型Duncan-Chang model9. 本构模型动剪切强度9. 本构模型非线性弹性模量nonlinear elastic model9. 本构模型盖帽模型cap model9. 本构模型刚塑性模型rigid plastic model9. 本构模型割线模量secant modulus9. 本构模型广义冯·米赛斯屈服准则extended von Mises yield criterion 9. 本构模型广义特雷斯卡屈服准则extended tresca yield criterion9. 本构模型加工软化work softening9. 本构模型加工硬化work hardening9. 本构模型加工硬化定律strain harding law9. 本构模型剑桥模型Cambridge model9. 本构模型柯西弹性模型Cauchy elastic model9. 本构模型拉特－邓肯模型Lade-Duncan model9. 本构模型拉特屈服准则Lade yield criterion9. 本构模型理想弹塑性模型ideal elastoplastic model9. 本构模型临界状态弹塑性模型critical state elastoplastic model9. 本构模型流变学模型rheological model9. 本构模型流动规则flow rule9. 本构模型摩尔－库仑屈服准则Mohr-Coulomb yield criterion9. 本构模型内蕴时间塑性模型endochronic plastic model9. 本构模型内蕴时间塑性理论endochronic theory9. 本构模型年粘弹性模型viscoelastic model9. 本构模型切线模量tangent modulus9. 本构模型清华弹塑性模型Tsinghua elastoplastic model9. 本构模型屈服面yield surface9. 本构模型沈珠江三重屈服面模型Shen Zhujiang three yield surface method 9. 本构模型双参数地基模型9. 本构模型双剪应力屈服模型twin shear stress yield criterion9. 本构模型双曲线模型hyperbolic model9. 本构模型松岗元－中井屈服准则Matsuoka-Nakai yield criterion9. 本构模型塑性形变理论9. 本构模型谈弹塑性模量矩阵elastoplastic modulus matrix9. 本构模型谈弹塑性模型elastoplastic modulus9. 本构模型谈弹塑性增量理论incremental elastoplastic theory9. 本构模型谈弹性半空间地基模型elastic half-space foundation model9. 本构模型谈弹性变形elastic deformation9. 本构模型谈弹性模量elastic modulus9. 本构模型谈弹性模型elastic model9. 本构模型魏汝龙－Khosla－Wu模型Wei Rulong-Khosla-Wu model9. 本构模型文克尔地基模型Winkler foundation model9. 本构模型修正剑桥模型modified cambridge model9. 本构模型准弹性模型hypoelastic model10. 地基承载力冲剪破坏punching shear failure10. 地基承载力次层（台）substratum10. 地基承载力地基subgrade, ground, foundation soil10. 地基承载力地基承载力bearing capacity of foundation soil10. 地基承载力地基极限承载力ultimate bearing capacity of foundation soil10. 地基承载力地基允许承载力allowable bearing capacity of foundation soil10. 地基承载力地基稳定性stability of foundation soil10. 地基承载力汉森地基承载力公式Hansen s ultimate bearing capacity formula10. 地基承载力极限平衡状态state of limit equilibrium10. 地基承载力加州承载比（美国）California Bearing Ratio10. 地基承载力局部剪切破坏local shear failure10. 地基承载力临塑荷载critical edge pressure10. 地基承载力梅耶霍夫极限承载力公式Meyerhof s ultimate bearing capacity formula 10. 地基承载力普朗特承载力理论Prandel bearing capacity theory10. 地基承载力斯肯普顿极限承载力公式Skempton s ultimate bearing capacity formula 10. 地基承载力太沙基承载力理论Terzaghi bearing capacity theory10. 地基承载力魏锡克极限承载力公式V esic s ultimate bearing capacity formula10. 地基承载力整体剪切破坏general shear failure11. 土压力被动土压力passive earth pressure11. 土压力被动土压力系数coefficient of passive earth pressure11. 土压力极限平衡状态state of limit equilibrium11. 土压力静止土压力earth pressue at rest11. 土压力静止土压力系数coefficient of earth pressur at rest11. 土压力库仑土压力理论Coulomb s earth pressure theory11. 土压力库尔曼图解法Culmannn construction11. 土压力朗肯土压力理论Rankine s earth pressure theory11. 土压力朗肯状态Rankine state11. 土压力谈弹性平衡状态state of elastic equilibrium11. 土压力土压力earth pressure11. 土压力主动土压力active earth pressure11. 土压力主动土压力系数coefficient of active earth pressure12. 土坡稳定分析安息角（台）angle of repose12. 土坡稳定分析毕肖普法Bishop method12. 土坡稳定分析边坡稳定安全系数safety factor of slope12. 土坡稳定分析不平衡推理传递法unbalanced thrust transmission method12. 土坡稳定分析费伦纽斯条分法Fellenius method of slices12. 土坡稳定分析库尔曼法Culmann method12. 土坡稳定分析摩擦圆法friction circle method12. 土坡稳定分析摩根斯坦－普拉斯法Morgenstern-Price method12. 土坡稳定分析铅直边坡的临界高度critical height of vertical slope12. 土坡稳定分析瑞典圆弧滑动法Swedish circle method12. 土坡稳定分析斯宾赛法Spencer method12. 土坡稳定分析泰勒法Taylor method12. 土坡稳定分析条分法slice method12. 土坡稳定分析土坡slope12. 土坡稳定分析土坡稳定分析slope stability analysis12. 土坡稳定分析土坡稳定极限分析法limit analysis method of slope stability 12. 土坡稳定分析土坡稳定极限平衡法limit equilibrium method of slope stability 12. 土坡稳定分析休止角angle of repose12. 土坡稳定分析扬布普遍条分法Janbu general slice method12. 土坡稳定分析圆弧分析法circular arc analysis13. 土的动力性质比阻尼容量specific gravity capacity13. 土的动力性质波的弥散特性dispersion of waves13. 土的动力性质波速法wave velocity method13. 土的动力性质材料阻尼material damping13. 土的动力性质初始液化initial liquefaction13. 土的动力性质地基固有周期natural period of soil site13. 土的动力性质动剪切模量dynamic shear modulus of soils13. 土的动力性质动力布西涅斯克解dynamic solution of Boussinesq13. 土的动力性质动力放大因素dynamic magnification factor13. 土的动力性质动力性质dynamic properties of soils13. 土的动力性质动强度dynamic strength of soils13. 土的动力性质骨架波akeleton waves in soils13. 土的动力性质几何阻尼geometric damping13. 土的动力性质抗液化强度liquefaction stress13. 土的动力性质孔隙流体波fluid wave in soil13. 土的动力性质损耗角loss angle13. 土的动力性质往返活动性reciprocating activity13. 土的动力性质无量纲频率dimensionless frequency13. 土的动力性质液化liquefaction13. 土的动力性质液化势评价evaluation of liquefaction potential13. 土的动力性质液化应力比stress ratio of liquefaction13. 土的动力性质应力波stress waves in soils13. 土的动力性质振陷dynamic settlement13. 土的动力性质阻尼damping of soil13. 土的动力性质阻尼比damping ratio14. 挡土墙挡土墙retaining wall14. 挡土墙挡土墙排水设施14. 挡土墙挡土墙稳定性stability of retaining wall14. 挡土墙垛式挡土墙14. 挡土墙扶垛式挡土墙counterfort retaining wall14. 挡土墙后垛墙（台）counterfort retaining wall14. 挡土墙基础墙foundation wall14. 挡土墙加筋土挡墙reinforced earth bulkhead14. 挡土墙锚定板挡土墙anchored plate retaining wall14. 挡土墙锚定式板桩墙anchored sheet pile wall14. 挡土墙锚杆式挡土墙anchor rod retaining wall14. 挡土墙悬壁式板桩墙cantilever sheet pile wall14. 挡土墙悬壁式挡土墙cantilever sheet pile wall14. 挡土墙重力式挡土墙gravity retaining wall15. 板桩结构物板桩sheet pile15. 板桩结构物板桩结构sheet pile structure15. 板桩结构物钢板桩steel sheet pile15. 板桩结构物钢筋混凝土板桩reinforced concrete sheet pile15. 板桩结构物钢桩steel pile15. 板桩结构物灌注桩cast-in-place pile15. 板桩结构物拉杆tie rod15. 板桩结构物锚定式板桩墙anchored sheet pile wall15. 板桩结构物锚固技术anchoring15. 板桩结构物锚座Anchorage15. 板桩结构物木板桩wooden sheet pile15. 板桩结构物木桩timber piles15. 板桩结构物悬壁式板桩墙cantilever sheet pile wall16. 基坑开挖与降水板桩围护sheet pile-braced cuts16. 基坑开挖与降水电渗法electro-osmotic drainage16. 基坑开挖与降水管涌piping16. 基坑开挖与降水基底隆起heave of base16. 基坑开挖与降水基坑降水dewatering16. 基坑开挖与降水基坑失稳instability (failure) of foundation pit16. 基坑开挖与降水基坑围护bracing of foundation pit16. 基坑开挖与降水减压井relief well16. 基坑开挖与降水降低地下水位法dewatering method16. 基坑开挖与降水井点系统well point system16. 基坑开挖与降水喷射井点eductor well point16. 基坑开挖与降水铅直边坡的临界高度critical height of vertical slope 16. 基坑开挖与降水砂沸sand boiling16. 基坑开挖与降水深井点deep well point16. 基坑开挖与降水真空井点vacuum well point16. 基坑开挖与降水支撑围护braced cuts17. 浅基础杯形基础17. 浅基础补偿性基础compensated foundation17. 浅基础持力层bearing stratum17. 浅基础次层（台）substratum17. 浅基础单独基础individual footing17. 浅基础倒梁法inverted beam method17. 浅基础刚性角pressure distribution angle of masonary foundation 17. 浅基础刚性基础rigid foundation17. 浅基础高杯口基础17. 浅基础基础埋置深度embeded depth of foundation17. 浅基础基床系数coefficient of subgrade reaction17. 浅基础基底附加应力net foundation pressure17. 浅基础交叉条形基础cross strip footing17. 浅基础接触压力contact pressure17. 浅基础静定分析法（浅基础）static analysis (shallow foundation)17. 浅基础壳体基础shell foundation17. 浅基础扩展基础spread footing17. 浅基础片筏基础mat foundation17. 浅基础浅基础shallow foundation17. 浅基础墙下条形基础17. 浅基础热摩奇金法Zemochkin s method17. 浅基础柔性基础flexible foundation17. 浅基础上部结构－基础－土共同作用分析structure- foundation-soil interactionanalysis 17. 浅基础谈弹性地基梁（板）分析analysis of beams and slabs on elastic foundation 17. 浅基础条形基础strip footing17. 浅基础下卧层substratum17. 浅基础箱形基础box foundation17. 浅基础柱下条形基础18. 深基础贝诺托灌注桩Benoto cast-in-place pile18. 深基础波动方程分析Wave equation analysis18. 深基础场铸桩（台)cast-in-place pile18. 深基础沉管灌注桩diving casting cast-in-place pile18. 深基础沉井基础open-end caisson foundation18. 深基础沉箱基础box caisson foundation18. 深基础成孔灌注同步桩synchronous pile18. 深基础承台pile caps18. 深基础充盈系数fullness coefficient18. 深基础单桩承载力bearing capacity of single pile18. 深基础单桩横向极限承载力ultimate lateral resistance of single pile18. 深基础单桩竖向抗拔极限承载力vertical ultimate uplift resistance of single pile18. 深基础单桩竖向抗压容许承载力vertical ultimate carrying capacity of single pile18. 深基础单桩竖向抗压极限承载力vertical allowable load capacity of single pile18. 深基础低桩承台low pile cap18. 深基础地下连续墙diaphgram wall18. 深基础点承桩（台）end-bearing pile18. 深基础动力打桩公式dynamic pile driving formula18. 深基础端承桩end-bearing pile18. 深基础法兰基灌注桩Franki pile18. 深基础负摩擦力negative skin friction of pile18. 深基础钢筋混凝土预制桩precast reinforced concrete piles18. 深基础钢桩steel pile18. 深基础高桩承台high-rise pile cap18. 深基础灌注桩cast-in-place pile18. 深基础横向载荷桩laterally loaded vertical piles18. 深基础护壁泥浆slurry coat method18. 深基础回转钻孔灌注桩rotatory boring cast-in-place pile18. 深基础机挖异形灌注桩18. 深基础静力压桩silent piling18. 深基础抗拔桩uplift pile18. 深基础抗滑桩anti-slide pile18. 深基础摩擦桩friction pile18. 深基础木桩timber piles18. 深基础嵌岩灌注桩piles set into rock18. 深基础群桩pile groups18. 深基础群桩效率系数efficiency factor of pile groups18. 深基础群桩效应efficiency of pile groups18. 深基础群桩竖向极限承载力vertical ultimate load capacity of pile groups 18. 深基础深基础deep foundation18. 深基础竖直群桩横向极限承载力18. 深基础无桩靴夯扩灌注桩rammed bulb ile18. 深基础旋转挤压灌注桩18. 深基础桩piles18. 深基础桩基动测技术dynamic pile test18. 深基础钻孔墩基础drilled-pier foundation18. 深基础钻孔扩底灌注桩under-reamed bored pile18. 深基础钻孔压注桩starsol enbesol pile18. 深基础最后贯入度final set19. 地基处理表层压密法surface compaction19. 地基处理超载预压surcharge preloading19. 地基处理袋装砂井sand wick19. 地基处理地工织物geofabric, geotextile19. 地基处理地基处理ground treatment, foundation treatment19. 地基处理电动化学灌浆electrochemical grouting19. 地基处理电渗法electro-osmotic drainage19. 地基处理顶升纠偏法19. 地基处理定喷directional jet grouting19. 地基处理冻土地基处理frozen foundation improvement19. 地基处理短桩处理treatment with short pile19. 地基处理堆载预压法preloading19. 地基处理粉体喷射深层搅拌法powder deep mixing method19. 地基处理复合地基composite foundation19. 地基处理干振成孔灌注桩vibratory bored pile19. 地基处理高压喷射注浆法jet grounting19. 地基处理灌浆材料injection material19. 地基处理灌浆法grouting19. 地基处理硅化法silicification19. 地基处理夯实桩compacting pile19. 地基处理化学灌浆chemical grouting19. 地基处理换填法cushion19. 地基处理灰土桩lime soil pile19. 地基处理基础加压纠偏法19. 地基处理挤密灌浆compaction grouting19. 地基处理挤密桩compaction pile, compacted column19. 地基处理挤淤法displacement method19. 地基处理加筋法reinforcement method19. 地基处理加筋土reinforced earth19. 地基处理碱液法soda solution grouting19. 地基处理浆液深层搅拌法grout deep mixing method19. 地基处理降低地下水位法dewatering method19. 地基处理纠偏技术19. 地基处理坑式托换pit underpinning19. 地基处理冷热处理法freezing and heating19. 地基处理锚固技术anchoring19. 地基处理锚杆静压桩托换anchor pile underpinning19. 地基处理排水固结法consolidation19. 地基处理膨胀土地基处理expansive foundation treatment19. 地基处理劈裂灌浆fracture grouting19. 地基处理浅层处理shallow treatment19. 地基处理强夯法dynamic compaction19. 地基处理人工地基artificial foundation19. 地基处理容许灌浆压力allowable grouting pressure19. 地基处理褥垫pillow19. 地基处理软土地基soft clay ground19. 地基处理砂井sand drain19. 地基处理砂井地基平均固结度average degree of consolidation of sand-drained ground 19. 地基处理砂桩sand column19. 地基处理山区地基处理foundation treatment in mountain area19. 地基处理深层搅拌法deep mixing method19. 地基处理渗入性灌浆seep-in grouting19. 地基处理湿陷性黄土地基处理collapsible loess treatment19. 地基处理石灰系深层搅拌法lime deep mixing method19. 地基处理石灰桩lime column, limepile19. 地基处理树根桩root pile19. 地基处理水泥土水泥掺合比cement mixing ratio19. 地基处理水泥系深层搅拌法cement deep mixing method19. 地基处理水平旋喷horizontal jet grouting19. 地基处理塑料排水带plastic drain19. 地基处理碎石桩gravel pile, stone pillar19. 地基处理掏土纠偏法19. 地基处理天然地基natural foundation19. 地基处理土工聚合物Geopolymer19. 地基处理土工织物geofabric, geotextile19. 地基处理土桩earth pile19. 地基处理托换技术underpinning technique19. 地基处理外掺剂additive19. 地基处理旋喷jet grouting19. 地基处理药液灌浆chemical grouting19. 地基处理预浸水法presoaking19. 地基处理预压法preloading19. 地基处理真空预压vacuum preloading19. 地基处理振冲法vibroflotation method19. 地基处理振冲密实法vibro-compaction19. 地基处理振冲碎石桩vibro replacement stone column19. 地基处理振冲置换法vibro-replacement19. 地基处理振密、挤密法vibro-densification, compacting19. 地基处理置换率（复合地基）replacement ratio19. 地基处理重锤夯实法tamping19. 地基处理桩式托换pile underpinning19. 地基处理桩土应力比stress ratio20. 动力机器基础比阻尼容量specific gravity capacity20. 动力机器基础等效集总参数法constant strain rate consolidation test20. 动力机器基础地基固有周期natural period of soil site20. 动力机器基础动基床反力法dynamic subgrade reaction method20. 动力机器基础动力放大因素dynamic magnification factor20. 动力机器基础隔振isolation20. 动力机器基础基础振动foundation vibration20. 动力机器基础基础振动半空间理论elastic half-space theory of foundation vibr ation20. 动力机器基础基础振动容许振幅allowable amplitude of foundation vibration 20. 动力机器基础基础自振频率natural frequency of foundation20. 动力机器基础集总参数法lumped parameter method20. 动力机器基础吸收系数absorption coefficient20. 动力机器基础质量－弹簧－阻尼器系统mass-spring-dushpot system21. 地基基础抗震地基固有周期natural period of soil site21. 地基基础抗震地震earthquake, seism, temblor21. 地基基础抗震地震持续时间duration of earthquake21. 地基基础抗震地震等效均匀剪应力equivalent even shear stress of earthquake 21. 地基基础抗震地震反应谱earthquake response spectrum21. 地基基础抗震地震烈度earthquake intensity21. 地基基础抗震地震震级earthquake magnitude21. 地基基础抗震地震卓越周期seismic predominant period21. 地基基础抗震地震最大加速度maximum acceleration of earthquake21. 地基基础抗震动力放大因数dynamic magnification factor21. 地基基础抗震对数递减率logrithmic decrement21. 地基基础抗震刚性系数coefficient of rigidity21. 地基基础抗震吸收系数absorption coefficient22. 室内土工试验比重试验specific gravity test22. 室内土工试验变水头渗透试验falling head permeability test22. 室内土工试验不固结不排水试验unconsolidated-undrained triaxial test22. 室内土工试验常规固结试验routine consolidation test22. 室内土工试验常水头渗透试验constant head permeability test22. 室内土工试验单剪仪simple shear apparatus22. 室内土工试验单轴拉伸试验uniaxial tensile test22. 室内土工试验等速加荷固结试验constant loading rate consolidatin test22. 室内土工试验等梯度固结试验constant gradient consolidation test22. 室内土工试验等应变速率固结试验equivalent lumped parameter method22. 室内土工试验反复直剪强度试验repeated direct shear test22. 室内土工试验反压饱和法back pressure saturation method22. 室内土工试验高压固结试验high pressure consolidation test22. 室内土工试验各向不等压固结不排水试验consoidated anisotropically undrained test 22. 室内土工试验各向不等压固结排水试验consolidated anisotropically drained test 22. 室内土工试验共振柱试验resonant column test22. 室内土工试验固结不排水试验consolidated undrained triaxial test22. 室内土工试验固结快剪试验consolidated quick direct shear test22. 室内土工试验固结排水试验consolidated drained triaxial test22. 室内土工试验固结试验consolidation test22. 室内土工试验含水量试验water content test22. 室内土工试验环剪试验ring shear test22. 室内土工试验黄土湿陷试验loess collapsibility test22. 室内土工试验击实试验22. 室内土工试验界限含水量试验Atterberg limits test22. 室内土工试验卡萨格兰德法Casagrande s method22. 室内土工试验颗粒分析试验grain size analysis test22. 室内土工试验孔隙水压力消散试验pore pressure dissipation test22. 室内土工试验快剪试验quick direct shear test22. 室内土工试验快速固结试验fast consolidation test22. 室内土工试验离心模型试验centrifugal model test22. 室内土工试验连续加荷固结试验continual loading test22. 室内土工试验慢剪试验consolidated drained direct shear test22. 室内土工试验毛细管上升高度试验capillary rise test22. 室内土工试验密度试验density test22. 室内土工试验扭剪仪torsion shear apparatus22. 室内土工试验膨胀率试验swelling rate test22. 室内土工试验平面应变仪plane strain apparatus22. 室内土工试验三轴伸长试验triaxial extension test22. 室内土工试验三轴压缩试验triaxial compression test22. 室内土工试验砂的相对密实度试验sand relative density test22. 室内土工试验筛分析sieve analysis。
土木工程外文翻译资料
Reinforced ConcretePlain concrete is formed from a hardened mixture ofcement ,water ,fine aggregate, coarse aggregate (crushed stone or gravel),air, and often other admixtures. The plastic mix is placed and consolidated in the formwork, then cured to facilitate the acceleration of the chemical hydration reaction lf the cement/water mix, resulting in hardened concrete. The finished product has high compressive strength, and low resistance to tension, such that its tensile strength is approximately one tenth lf its compressive strength. Consequently, tensile and shear reinforcement in the tensile regions of sections has to be provided to compensate for the weak tension regions in the reinforced concrete element.It is this deviation in the composition of a reinforces concrete section from the homogeneity of standard wood or steel sections that requires a modified approach to the basic principles of structural design. The two components of the heterogeneous reinforced concrete section are to be so arranged and proportioned that optimal use is made of the materials involved. This is possible because concrete can easily be given any desired shape by placing and compacting the wet mixture of the constituent ingredients are properly proportioned, the finished product becomes strong, durable, and, in combination with the reinforcing bars, adaptable for use as main members of any structural system.The techniques necessary for placing concrete depend on the type of member to be cast: that is, whether it is a column, a bean, a wall, a slab, a foundation. a mass columns, or an extension of previously placed and hardened concrete. For beams, columns, and walls, the forms should be well oiled after cleaning them, and the reinforcement should be cleared of rust and other harmful materials. In foundations, the earth should be compacted and thoroughly moistened to about 6 in. in depth to avoid absorption ofthe moisture present in the wet concrete. Concrete should always be placed in horizontal layers which are compacted by means of high frequency power-driven vibrators of either the immersion or external type, as the case requires, unless it is placed by pumping. It must be kept in mind, however, that over vibration can be harmful since it could cause segregation of the aggregate and bleeding of the concrete.Hydration of the cement takes place in the presence of moisture at temperatures above 50°F. It is necessary to maintain such a condition in order that the chemical hydration reaction can take place. If drying is too rapid, surface cracking takes place. This would result in reduction of concrete strength due to cracking as well as the failure to attain full chemical hydration.It is clear that a large number of parameters have to be dealt with in proportioning a reinforced concrete element, such as geometrical width, depth, area of reinforcement, steel strain, concrete strain, steel stress, and so on. Consequently, trial and adjustment is necessary in the choice of concrete sections, with assumptions based on conditions at site, availability of the constituent materials, particular demands of the owners, architectural and headroom requirements, the applicable codes, and environmental reinforced concrete is often a site-constructed composite, in contrast to the standard mill-fabricated beam and column sections in steel structures.A trial section has to be chosen for each critical location in a structural system. The trial section has to be analyzed to determine if its nominal resisting strength is adequate to carry the applied factored load. Since more than one trial is often necessary to arrive at the required section, the first design input step generates into a series of trial-and-adjustment analyses.The trial-and –adjustment procedures for the choice of a concretesection lead to the convergence of analysis and design. Hence every design is an analysis once a trial section is chosen. The availability of handbooks, charts, and personal computers and programs supports this approach as a more efficient, compact, and speedy instructional method compared with the traditional approach of treating the analysis of reinforced concrete separately from pure design.EarthworkBecause earthmoving methods and costs change more quickly than those in any other branch of civil engineering, this is a field where there are real opportunities for the enthusiast. In 1935 most of the methods now in use for carrying and excavating earth with rubber-tyred equipment did not exist. Most earth was moved by narrow rail track, now relatively rare, and the main methods of excavation, with face shovel, backacter, or dragline or grab, though they are still widely used are only a few of the many current methods. To keep his knowledge of earthmoving equipment up to date an engineer must therefore spend tine studying modern machines. Generally the only reliable up-to-date information on excavators, loaders and transport is obtainable from the makers.Earthworks or earthmoving means cutting into ground where its surface is too high ( cuts ), and dumping the earth in other places where the surface is too low ( fills). Toreduce earthwork costs, the volume of the fills should be equal to the volume of the cuts and wherever possible the cuts should be placednear to fills of equal volume so as to reduce transport and double handlingof the fill. This work of earthwork design falls on the engineer who lays out the road since it is the layout of the earthwork more than anything else which decides its cheapness. From the available maps ahd levels, the engineering must try to reach as many decisions as possible in the drawing office by drawing cross sections of the earthwork. On the site when further information becomes available hecan make changes in jis sections and layout,but the drawing lffice work will not have been lost. It will have helped him to reach the best solution in the shortest time.The cheapest way of moving earth is to take it directly out of the cut and drop it as fill with the same machine. This is not always possible, but when it canbe done it is ideal, being both quick and cheap. Draglines, bulldozers and face shovels an do this. The largest radius is obtained with the dragline,and the largest tonnage of earth is moved by the bulldozer, though only over short distances.The disadvantages of the dragline are that it must dig below itself, it cannot dig with force into compacted material, it cannot dig on steep slopws, and its dumping and digging are not accurate.Face shovels are between bulldozers and draglines, having a larger radius of action than bulldozers but less than draglines. They are anle to dig into a vertical cliff face in a way which would be dangerous tor a bulldozer operator and impossible for a dragline. Each piece of equipment should be level of their tracks and for deep digs in compact material a backacter is most useful, but its dumping radius is considerably less than that of the same escavator fitted with a face shovel.Rubber-tyred bowl scrapers are indispensable for fairly level digging where the distance of transport is too much tor a dragline or face shovel. They can dig the material deeply ( but only below themselves ) to a fairly flat surface, carry it hundreds of meters if need be, then drop it and level it roughly during the dumping. For hard digging it is often found economical to keep a pusher tractor ( wheeled or tracked ) on the digging site, to push each scraper as it returns to dig. As soon as the scraper is full,the pusher tractor returns to the beginning of the dig to heop to help the nest scraper.Bowl scrapers are often extremely powerful machines;many makers build scrapers of 8 cubic meters struck capacity, which carry 10 m ³ heaped. The largest self-propelled scrapers are of 19 m ³ struck capacity ( 25 m ³ heaped )and they are driven by a tractor engine of 430 horse-powers.Dumpers are probably the commonest rubber-tyred transport since they can also conveniently be used for carrying concrete or other building materials. Dumpers have the earth container over the front axle on large rubber-tyred wheels, and the container tips forwards on most types, though in articulated dumpers the direction of tip can be widely varied. The smallest dumpers have a capacity of about 0.5 m ³, and the largest standard types are of about 4.5 m ³. Special types include the self-loading dumper of up to 4 m ³ and the articulated type of about 0.5 m ³. The distinction between dumpers and dump trucks must be remembered .dumpers tip forwards and the driver sits behind the load. Dump trucks are heavy, strengthened tipping lorries, the driver travels in front lf the load and the load is dumped behind him, so they are sometimes called rear-dump trucks.Safety of StructuresThe principal scope of specifications is to provide general principles and computational methods in order to verify safety of structures. The “ safety factor ”, which according to modern trends is independent of the nature and combination of the materials used, can usually be defined as the ratio between the conditions. This ratio is also proportional to the inverse of the probability ( risk ) of failure of the structure.Failure has to be considered not only as overall collapse of the structure but also as unserviceability or, according to a more precise. Common definition. As the reaching of a “ limit state ” which causes the construction not to accomplish the task it was designed for. There are two categories of limit state :(1)Ultimate limit sate, which corresponds to the highest value of the load-bearing capacity. Examples include local buckling or global instability of the structure; failure of some sections and subsequent transformation of the structure into a mechanism; failure by fatigue; elastic or plastic deformation or creep that cause a substantial change of the geometry of the structure; and sensitivity of the structure to alternating loads, to fire and to explosions.(2)Service limit states, which are functions of the use and durability of the structure. Examples include excessive deformations and displacements without instability; early or excessive cracks; large vibrations; and corrosion.Computational methods used to verify structures with respect to the different safety conditions can be separated into:(1)Deterministic methods, in which the main parameters are considered as nonrandom parameters.(2)Probabilistic methods, in which the main parameters are considered as random parameters.Alternatively, with respect to the different use of factors of safety, computational methods can be separated into:(1)Allowable stress method, in which the stresses computed under maximum loads are compared with the strength of the material reduced by given safety factors.(2)Limit states method, in which the structure may be proportioned on the basis of its maximum strength. This strength, as determined by rational analysis, shall not be less than that required to support a factored load equal to the sum of the factored live load and dead load ( ultimate state ).The stresses corresponding to working ( service ) conditions with unfactored live and dead loads are compared with prescribed values( service limit state ) . From the four possible combinations of the first two and second two methods, we can obtain some useful computational methods. Generally, two combinations prevail:(1)deterministic methods, which make use of allowable stresses.(2)Probabilistic methods, which make use of limit states.The main advantage of probabilistic approaches is that, at least in theory, it is possible to scientifically take into account all random factors of safety, which are then combined to define the safety factor. probabilistic approaches depend upon :(1)Random distribution of strength of materials with respect to the conditions of fabrication and erection ( scatter of the values of mechanical properties through out the structure );(2)Uncertainty of the geometry of the cross-section sand of the structure ( faults and imperfections due to fabrication and erection of the structure );(3)Uncertainty of the predicted live loads and dead loads acting on the structure;(4)Uncertainty related to the approximation of the computational method used ( deviation of the actual stresses from computed stresses ).Furthermore, probabilistic theories mean that the allowable risk can be based on several factors, such as :(1)Importance of the construction and gravity of the damage by its failure;(2)Number of human lives which can be threatened by this failure;(3)Possibility and/or likelihood of repairing the structure;(4)Predicted life of the structure.All these factors are related to economic and social considerations such as：(1)Initial cost of the construction;(2)Amortization funds for the duration of the construction;(3)Cost of physical and material damage due to the failure of the construction;(4)Adverse impact on society;(5)Moral and psychological views.The definition of all these parameters, for a given safety factor, allows construction at the optimum cost. However, the difficulty of carrying out a complete probabilistic analysis has to be taken into account. For such an analysis the laws of the distribution of the live load and its induced stresses, of the scatter of mechanical properties of materials, and of the geometry of the cross-sections and the structure have to be known. Furthermore, it is difficult to interpret the interaction between the law of distribution of strength and that of stresses because both depend upon the nature of the material, on the cross-sections and upon the load acting on the structure. These practical difficulties can be overcome in two ways. The first is to apply different safety factors to the material and to the loads, without necessarily adopting the probabilistic criterion. The second is an approximate probabilistic method which introduces some simplifying assumptions ( semi-probabilistic methods ) .。
土木工程外文翻译5
附录（一）外文原文4.2.1.1 C ement Test by Sieve No. 170The fineness of cement affects the quality of the concrete industry in general. A big cement particle cannot completely react with water as water cannot reach a remaining core in the cement particle. The water propagates through the cement particles and they start to dehydrate, which causes an increase in temperature, which is the main reason for the forming of hair cracks and preventing stabilization of cement volume. As a result, an increase in the cement particle size reduces the strength of the same cement content and increasing the fineness of the cement will improve the workability,cohesion, and durability with time and decrease the water moving upward to the concrete surface.Figure 4.1, from Neville’s book (1983), presents the relation between concrete strength and the concrete fineness at different ages. To perform this test, take a sample of 50 g of cement and shake it in a closed glass bottle for two minutes and then revolve the sample gently using dry bar. Put the sample in a closed bottle and leaveit for two minutes. Put the sample in 170 sieve (90 microns) and move it, shakingthe sieve horizontally and rotationally, then confirm finishing the sieve test when the rate of passing cement particles is not more than 0.5 g/min during the sieve process. Remove the fines carefully from the bottom of the sieve using a smooth brush. Then, collect and weigh the remaining particles on the sieve (W1).Repeat the same test with another sample. Then the residual weight for the second test is obtained (W2). Calculate the values of the remaining samples throughR1 = (W1/50) ×100R2 = (W2/50) ×100The ratio (R) is calculated by taking the average of R1 and R2 to the nearest 0.1% and, in the case of deviating results of the two samples, more than 1%. Do the test a third time and take the average of the three results.You can accept or refuse the cement based on the following condition:For Portland cement t •he R must not exceed than 10%.•For rapid hardening Portland cement the R must not exceed 5%.4.2.1.2 Initial and Final Setting Times of CementPaste Using Vicat ApparatusThe objective of this test is to define the time for initial and final setting of the paste of water and cement with standard consistency by using a Vicat apparatus and determinewhether the cement is expired or can be used.The initial setting is the required time to set and after that concrete cannot be poured or formed; the final setting time is the time required for the concrete to be hardened.Vicat apparatus (Figure 4.2) consists of a carrier with needle acting under a prescribed weight. The parts move vertically without friction and are not subject to erosionor corrosion. The paste mold is made from a metal or hard rubber or plastic likea cut cone with depth of 40 ±2 mm and the internal diameter of the upper face 70 ±5 mm and lower face 80 ±5 mm and provides a template of glass or similar materialsin the softer surface. Its dimensions are greater than the dimensions of the mold.The needle is used to determine the initial setting time in a steel cylinder with effective length 50 ±1 mm and diameter 1.13 ±0.5 mm. The needle measuring timeis in the form of a cylinder with length of 30 ±1 mm and diameter 1.13 ±0.5 mm andheld by a 5 mm diameter ring at the free end to achieve distance between the end of the needle and the ring of 0.5 mm.The test starts by taking a sample weighing about 400 g and placing it on an impermeable surface and then adding 100 ml of water and recording zero measurementfrom the time of adding water to the cement and then mixing for 240 + 5 secondson the impermeable surface.To determine the initial setting time and calibrate the device until the needle reaches the base of the mold, then adjust the measuring device to zero and return needle to its original place.Fill the mold with cement paste with standard consistency and troll the surface,then put the mold for a short time in a place that has the the temperature and humidity required for the test.Specific Surface (Wagner)-m2/kg365 days90 days28 days7 days20150 200 250 300304050Compressive Strength, MpaTransfer the mold to the apparatus under the needle, and then make the needleslowly approach the surface until it touches the paste’s surface, stop it in place fora second or two seconds to avoid impact of primary speed, then allow the moving parts to implement the needle vertically in the paste.Grading depends on when the needle stops penetrating or after 30 seconds, whichever is earlier, and indicates the distance between the mold base and the end of the needle, as well as the time start from the zero level measurement.Repeat the process of immersing the needle in the same paste in different locations with the distance between the immersing point and the edge of the mold orbetween two immersing points not less 10 mm after about 10 minutes, and clean the needle immediately after each test.Record time is measured from zero up to 5 ±1 mm from the base of the mold as the initial setting time to the nearest 5 minutes. Ensuring the accuracy of measurement of time between tests reduces embedment and the fluctuation of successivetests. The needle is used to identify the final time of setting; follow the same stepsas in determining time of initial setting and increase the period between embedment tests to 30 minutes.Record the time from zero measurement until embedment of the needle to a distance of 0.5 mm, which will be the final setting time. Control the impact of theneedle on the surface of the sample so the final setting time presents the effect ofthe needle. To enhance the test’s accuracy reduce the time between embedment tests and examine the fluctuation of these successive tests. Record the final setting timeto the nearest 5 mm.According to the Egyptian specifications the initial setting time must not be lessthan 45 minutes for all types of cement except the low heat cement, for which the initial setting time must not be less 60 minutes. The final setting time must be shorter than 10 hours for all types of cement.4.2.1.3 D ensity of CementThe purpose of this test is to determine the density of cement by identifying the weight and unit volume of the material by using the Le Chatelier density bottle. The determination of the cement density is essential for concrete mix design and to control its quality. This test follows specifications of the American Society for Testingand Materials, ASTM C188-84.The Le Chatelier device is a standard round bottle. Its shape and dimensions are shown in Figure 4.3. This bottle must have all the required dimensions, lengths, and uniform degradation and accuracy.The glass that is used in the Le Chatelier bottle must be of high quality and freefrom any defects. It should not interact with chemicals and have high resistance to heat and appropriate thickness to have a high resistance to crushing. Measurements start at the bottle’s neck and go from zero to 1 mL and from 18 to 24 mL with accuracyto 0.1 mL. Each bottle must have a number to distinguish it from any other.Write on the bottle the standard temperature and the capacity in millimeters over the highest point of grading.Processed sample cement weighing about 64 g to the nearest 0.05 g must be tested.Fill the bottle with kerosene free from water and oil whose density is at least 62 API. Up to point gradations between zero and 1 mL, dry the inner surface of the bottle at the highest level of kerosene if necessary, and use rubber on the surface of the table used for the test when filling the bottle.The bottle, which is filled with kerosene, is placed in a water bath and the firstreading to kerosene level is recorded. To record the first reading correctly install the bottle in the water bath vertically. Put a cement sample weighing 64 g with accuracy to 0.05 g inside the bottle with small batches at the same temperature of kerosene, taking into account when putting the cement inside the bottle to avoid cement droppingout or its adhesion on the internal surfaces of the bottle at the highest level. The bottle can be placed on the vibrating machine when putting the cement inside the bottle to expedite the process and prevent adhesion of granulated cement with the internal surfaces of the bottle.After laying the cement inside the bottle, put a cap on the bottle mouth and then spin diagonally on the surface so as to expel the air between the granules of cement, and continue moving the bottle until the emergence of air bubbles stops from the kerosene surface inside the bottle.Put the bottle in the water bath and then take the final reading, and record the reading at the lower surface of kerosene so as to avoid the impact of surface tension. For the first and final readings, make sure that the bottle is placed in a water bath with constant temperature for a period not to exceed the difference in temperature between the first and final readings of about 0.2°C.The difference between the first and final reading is the volume of the moving liquid by the cement sample.The volume of the moving liquid = final reading –first reading4.2.1.4 D efine Cement Fineness by Using Blaine ApparatusThis test is used to determine the surface area by comparing the test sample with the specific reference. The greater surface area increases the speed of concrete hardening and obtains early strength. This test determines the acceptance of the cement. There are many tests to define cement fineness and one is a Blaine apparatus as stated in many codes such as the Egyptian code.This test depends on calculating the surface area by comparing the sample test and the reference sample using a Blaine apparatus to determine the time required to pass a definite quantity of air inside a cement layer with defined dimensions and porosity.A Blaine apparatus is shown in Figure 4.4. The first step in testing is to determine the volume of the cement layer using mercury in the ring device of the Blaine apparatus.Cement is then added and by knowing the weight of the cement before andafter adding it as well as the mercury density, the volume of the cement layer can be calculated.V = W1 –W2/DmwhereV is the volume of cement layer, cm3.Fi gure 4.4 Blaine apparatus.Concrete Materials and Tests 111W1 is the weight of mercury in grams that fills the device to nearest (0.0 g).W2 is the weight of mercury in grams that fills the device to nearest (0.0 g).Dm is the density of the mercury (g/cm3). From tables, define the mercury densityat the average temperature of the test by using the manometer in the Blaine apparatus.From the previous equation:Sr is the reference cement surface area, (cm2/g).Dr is the reference cement density (g/cm3).Pr is the porosity of the cement layer.Ir is the air visciosity in the average temperature for reference cement test.Tr is the average time required for the manometer liquid to settle in two marksto nearest 0.2 sec.K is the Blaine apparatus constant factor defined by the previous equation by knowing the time needed to pass the air in the sample.To retest the sample, we calculate its surface area by using the following equation:Sc = Sr(Dr/Dc) *(Tc/Tr)^0.5According to the Egyptian code, the acceptance and refusal of cement is based on limites shown in Table 4.2.Table 4.2Cement Fineness Acceptance andRefusal LimitsCement TypesCement Fineness Not LessThan cm2/gmOrdinary Portland 2750Rapid hardening Portland 3500Sulfate resistant Portland 2800Low heat Portland 2800White Portland 2700Mixing sand Portland 30004100 fineness 4100Slag Portland 25004.2.1.5 C ompressive Strength of Cement MortarsThe cement mortar compressive strength test is performed using standard cubesof cement mortar mixed manually and compacted mechanically using a standard vibrating machine. This test is considered a refusal or acceptance determination. Compressive strength is one of the most important properties of concrete. The concrete gains its compressive strength from cement paste as a result of the interactionbetween the cement and water added to the mix. So it is critical to make sure that the cement used is the appropriate compressive strength. This test should be done to all types of cement.Needed for the test are stainless steel sieves with standard square holes opened 850 or 650 microns. Stainless steel does not react with cement and weighs 210 g. The vibrating machine has a weight of about 29 kg and the speed of vibration is about 12,000 vertical vibrations + 400 RPM and the moment of vibrating column is0.016 N.m.The mold of the test is a cube 70.7 ±1 mm, the surface area for each surface is500 mm2, the acceptable tolerance in leveling is about 0.03 mm, and the tolerance between paralleling for each face is about 0.06 mm.The mold is manufactured from materials that will not react with the cement mortar, and the base of the mold is made from steel that can prevent leaks of the mortaror water from the mold. The base is matched with the vibrating machine.The sand should contain a percentage of silica not less than 90% by weight andmust be washed and dried very well. Moreover, the humidity of the sand must not be more than 0.1% by weight for it to pass through a sieve with openings of 850 microns, and for it to pass through the standard sieve size of 600 microns it should not have more than 10% humidity by weight (Tables 4.3 and 4.4).After performing the tests, the standard cubes will be crushed within one day,which is about 24 ±0.5 hours, and three days in the limits of 72 ±1 hour, and afterseven days within 168 ±1 hour, and after 28 days within 672 ±1 hour.Table 4.5 illustrates the limits of acceptance and rejection according to the cement mortar compressive strength. Note from the table that there is more than one typeof high-alumina cement as the types vary according to the percentage of oxide alumina.The compressive strength after 28 days will not be considered accepted orrejected unless clearly stated in the contract between the supplier and the client（二）外文原文翻译4.2.1.1水泥试验筛170号水泥的优质一般影响混凝土行业的质量。
土木工程英文翻译
【例1.1】Civil engineering offers a particular challenge , because almost every structure orsystem that is designed and built by civil engineers is unique.One structure rarely duplicatesanother exactly.译文:土木工程提出了特殊的挑战,因为由土木工程师设计建造的每个结构或系统几乎都是唯一的。
一个结构几乎不能完全复制另一个【例1.5】If the structure is saved or returned to its original state , additional foundationsupport must be provided.译文:假如建筑物要加以补救或恢复原貌,对基础做支护加固则是非常必要的。
为了使句子简洁精炼,专业英语中大量使用不定式.动名词、分词。
【例1.6】The total weight being less , it is possible to build much taller buildings.译文:由于总重量减轻,就有可能建造更高的楼房。
【例1.7】All the material forming the crust of the earth likely to be affected by the pressureof structures is divided by engineers into two major groups : rocks and soils.译文:受建筑物压力作用的地壳材料被工程人员分成两组,即岩石和土。
【例1.8】Compared with structural materials , such as steel and timber , soil is difficult to investigate scientifically.译文:与钢材、木材等建筑材料相比较,土研究起来颇为困难。
土木施工外文翻译
土木施工外文翻译Lesson 1 Civil Engineering——土木工程土木工程是最古老的工程专业之一，它包括对建筑外界的规划、设计、施工以及管理。
建筑外界包括从灌溉排水系统到火箭发射设施在内的所有按科学原理建造的结构物。
土木工程师修建道路、桥梁、隧道、大坝、港口、发电厂、给排水系统、医院、学校、公共交通等公共设施，这些是现代社会和人口密集地所必需的。
他们也修建私有设施，如飞机场、铁路、管道、摩天大楼等工业、商业或居住用的大型结构物。
另外，土木工程师规划、设计和建造完整的城镇，最近还设计了设备齐全的空间站。
单词“ civil”来自于拉丁文中的“citizen”。
1872年，英国人John Smeaton 采用这一术语把他的民用工程与那时占主导地位的的军事工程区别开来。
从此，“土木工程”经常用于指修建公共设施的工程师的工作领域，虽然“土木工程”所包含的领域要宽广得多。
——范围土木工程工作范围很广，因此可以把土木工程细分为许多技术专业。
不同类型的项目可能需要许多技术专业土木工程师的技术合作。
开始一个项目时，负责功能（给水、排水、电力管线）布置的工程师对工地进行测量并绘制成图；土工专家进行土壤试验以确定泥土是否可以承受得住结构物重量；环境专家研究工程对当地的影响，包括空气和地下水的可能污染，对当地动植物的影响以及如何设计以达到政府旨在保护环境的要求；交通工程专家选择交通设施类型以缓解项目竣工时对当地道路和其它交通网络所增加的负担；同时，结构专家利用初步数据进行细部设计、整体设计和工程说明制定。
从工程开始到完工，由工程管理专家统一管理、协调这些土木工程师的工作。
在其他专家提供的信息的基础上，工程管理人员预算人工、材料的数量和费用，安排所有的工作进度，订购材料和设备，雇佣承包人和分包人，以及其它的工程管理以确保工程保质保量按时完成。
任何项目中土木工程师都广泛应用到计算机。
计算机（指计算机辅助设计或CAD）被用于设计工程的各种单元和管理工程。
土木工程外文文献翻译(含中英文)
Experimental research on seismic behavior of abnormal jointin reinforced concrete frameAbstract :Based on nine plane abnormal joint s , one space abnormal joint experiment and a p seudo dynamic test of a powerplant model , the work mechanism and the hysteretic characteristic of abnormal joint are put to analysis in this paper. A conception of minor core determined by the small beam and small column , and a conclusion that the shear capacity of ab2normal joint depends on minor core are put forward in this paper. This paper also analyzes the effect s of axial compres2 sion , horizontal stirrup s and section variation of beam and column on the shear behavior of abnormal joint . Finally , the formula of shear capacity for abnormal joint in reinforced concrete f rame is provided.Key words : abnormal j oint ; minor core ; seismic behavior ; shear ca paci t yCLC number :TU375. 4 ; TU317. 1 Document code :A Article ID :100627930 (2006) 022*******1 Int roductionFor reinforced concrete f rame st ructure , t he joint is a key component . It is subjected to axialcomp ression , bending moment and shear force. The key is whet her the joint has enough shear capaci2ty. The Chinese Code f or S eismic Desi gn of B ui l di ngs ( GB5001122001) adopt s the following formulato calculate t he shear capacity of the reinforced concrete f rame joint .V j = 1. 1ηj f t b j h j + 0. 05ηj Nb jb c+ f yv A svjh b0 - a′ss(1)Where V j = design value of t he seismic shear capacity of the joint core section ;ηj = influential coefficient of t he orthogonal beam to the column ;f t = design value of concrete tensile st rength ;b j = effective widt h of the joint core section ;h j = dept h of the joint core section , Which can be adopted as t he depth of the column section int he verification direction ;N = design value of axial compression at t he bot tom of upper column wit h considering the combi2 nation of the eart hquake action , When N > 015 f c b c h c , let N = 0. 5 f c b c h c ;b c = widt h of t he column section ;f yv = design value of t he stirrup tensile st rengt h ;A svj = total stirrup area in a set making up one layer ;h b0 = effective dept h of t he beam.If t he dept h of two beams at the side of t he joint is unequal , h b0 = t he average depth of two beams.a′s = distance f rom the cent roid of the compression beam steel bar to the ext reme concrete fiber . s = distance of t he stirrup .Eq. 1 is based on t he formula in t he previous seismiccode[1 ] and some modifications made eavlicr and it is suit2able to the normal joint of reinforced concrete f rame , butnot to t he abnormal one which has large different in t hesection of t he upper column and lower one (3 600 mm and1 200 mm) , lef t beam and right beam (1 800 mm and 1200 mm) . The shear capacity of abnormal joint s calculat2ed by Eq. 1 may cause some unsafe result s. A type of ab2normal joint which of ten exist s in t he power plant st ruc2t ure is discussed ( see Fig. 1) , and it s behavior was st ud2ied based on t he experiment in t his paper2 Experimental workAccording to the above problem , and t he experiment of plane abnormal joint s and space abnormal joint , a p seudo dynamic test of space model of power plant st ruct ure was carried out . The aim of t hisst udy is to set up a shear force formula and to discuss seismic behavior s of t he joint s.According to the characteristic of t he power plant st ruct ure , nine abnormal joint s and one space abnormal joint were designed in t he experiment . The scale of the model s is one2fif t h. Tab. 1 and Tab.2 show t he dimensions and reinforcement detail s of t he specimens.Fig. 2 shows the typical const ruction drawing of t he specimen. Fig. 3 shows the loading set up . These specimens are subjected to low2cyclic loading , the loading process of which is cont rolled by force and displacement , t he preceding yield loading by force and subsequent yield by t he displacement .The shear deformation of the joint core , t he st rain of the longit udinal steel and t he stirrup are main measuring items.3 Analysis of test result s3. 1 Main resultsTab. 3 shows t he main result s of t he experiment .3. 2 Failure process of specimenBased on t he experiment , t he process of t he specimens’failure includes four stages , namely , t he initial cracking , t he t horough cracking , the ultimate stage and t he failure stage.(1) Initial cracking stageWhen t he first diagonal crack appears along t he diagonal direction in t he core af ter loading , it s widt h is about 0. 1mm , which is named initial cracking stage of joint core. Before t he initial cracking stage , t he joint remains elastic performance , and the variety of stiff ness is not very obvious on t hep2Δcurve. At t his stage concrete bear s most of the core shear force while stirrup bears few. At t he timewhen t he initial crack occur s , t he st ress of t he stirrup at t he crack increase sharply and t he st rain is a2bout 200 ×10 - 6 —300 ×10 - 6 . The shear deformation of t he core at t his stage is very small (less than 1×10 - 3 radian ,generally between 0. 4 ×10 - 3 and 0. 8 ×10 - 3 radian) .(2) Thorough cracking stageWit h the load increasing following t he initial cracking stage , the second and t hird crossing diago2 nal cracks will appear at t he core. The core is cut into some small rhombus pieces which will become at least one main inclined crack across t he core diagonal . The widt h of cracks enlarges obviously , andt he wider ones are generally about 0. 5mm , which is named core t horough cracking stage. The st ress of stirrup increases obviously , and the stirrup in t he middle of t he core is near to yielding or has yiel2 ded. The joint core shows nonlinear property on t he p2Δcurve , and it enter s elastic2plastic stage. Theload at t horough cracking stage is about 80 % —90 % load.(3) Ultimate stageAt t his stage , t he widt h of t he cracks is about 1mm or more and some new cracks continue to oc2 cur . The shear deformation at t he core is much larger and concrete begins to collap se. Af ter several cyclic loading , the force reaches the maximum value , which is called ultimate stage. The load increase is due to t he enhancing of the concrete aggregate mechanical f riction between cracks. At t he same timet he st ress of stirrup increases gradually. On t he one hand stirrup resist s t he horizontal shear , and on t he ot her hand the confinement effect to t he expanding compression concrete st rengthens continuous2ly , which can also improve t he shear capacity of diagonal compression bar mechanism.(4) Failure stageAs the load circulated , concrete in t he core began to collap se , and t he deformation increased sharply , while the capacity began to drop . It was found t hat t he slip of reinforcement in t he beam wasvery serious in t he experiment . Wit h t he load and it s circulation time increasing , t he zoon wit houtbond gradually permeated towards t he internal core , enhancing t he burden of t he diagonal compressionbar mechanism and accelerates the compression failure of concrete. Fig. 4 shows t he p hotos of typical damaged joint s.A p seudo dynamic test of space model ofpower plant st ruct ure was carried out to researcht he working behavior of t he abnormal joint s in re2al st ructure and the seismic behavior of st ructure.Fig. 5 shows the p hoto of model .The test includes two step s. The fir st is thep seudo dynamic test . At t his step , El2Cent rowave is inp ut and the peak acceleration variesf rom 50 gal to 1 200 gal . The seismic response is measured. The second is t he p seudo static test . Theloading can’t stop until t he model fail s.Fig. 7 Minor coreThe experiment shows t hat t he dist ribution and development of t hecrack is influenced by t he rest rictive effect of the ort hogonal beam , andt he crack of joint core mainly dist ributes under t he orthogonal beam( see Fig. 6) , which is different f rom t he result of t he plane joint test ,but similar to J 4210.3. 3 Analysis of test results3. 3. 1 Mechanical analysisIn t he experiment , t he location of the initial crack of t he exteriorjoint and the crushed position of concrete both appear in the middle oft he joint core , and t he position is near t he centerline of t he upper col2umn. The initial crack and crushed position of t he concrete of the interior joint both appear in t he mi2 nor core ( see Fig. 4 ,Fig. 7) . For interior abnormal joint t he crack doesn’t appear or develop in t he ma2j or core out side of the mi nor core until t horough cracking takes place , while t he crack seldom appearsin t he shadow region ( see Fig. 7) as the joint fail s. Therefore , for abnormal joint , t he shear capacity oft he joint core depends on t he properties of t he mi nor core , namely , on t he st rengt h grades of concrete ,t he size and the reinforcement of t he mi nor core , get t he effect of t he maj or core dimension can’t be neglected.Mechanical effect s are t he same will that of t he normal joint , when t he forces t ransfer to t he mi2 nor core t hrough column and beam and reinforcement bar . Therefore , t he working mechanisms of nor2mal joint , including t russ mechanism , diagonal compression bar mechanism and rest rictive mechanismof stirrup , are also suitable for mi nor core of t he abnormal joint , but their working characteristic is not symmet rical when the load rever ses. Fig. 8 illust rates t he working mechanism of t he abnormal joint .When t he load t ransfer to mi nor core , t he diagonal compression bar area of mi nor core is biggert han normal joint core2composed by small column and small beam of abnormal joint , which is due to t he compressive st ress diff usion of concrete compressive region of the beam and column , while at t hesame time t he compression carried by the diagonal compression bar becomes large. Because t he main part of bond force of column and beam is added to t he diagonal comp ression bar but cont rasting wit h t he increased area of diagonal compression bar , t he increased action is small . The region in the maj orcore but out of the mi nor core has less st ress dist ribution and fewer cracks. The region can confine t heexpansion of t he concrete of t he mi nor core diagonal compression bar concrete , which enhances t he concrete compressive st rengt h of mi nor core diagonal compression bar .Making t he mi nor core as st udy element , the area increment of concrete diagonal compression barin mi nor core is related to t he st ress diff usion of t he beam and column compressive region. The magni2t ude of diff usion area is related to height difference of t he beam sections and column sections. Name2ly , it is related to t he size of mi nor core section and maj or core section. Thus , the increased shearst rengt h magnit ude caused by mi nor core rest rictive effect on maj or core can be measured quantitative2ly by t he ratio of maj or core area to mi nor core area. And it al so can be expressed that t he rest rictive effect is quantitatively related to t he ratio. Obviously , t he bigger t he ratio is and t he st ronger t he con2finement is , t he st ronger t he bearing capacity is.The region in the maj or core but under the mi nor core still need stirrup bar because of t he hori2 zontal force t ransferred by bigger beam bar . But force is small .3. 3. 2 load2displacement curves analysisFig. 9 shows t he typical load2displacement curves at t he beam end of t he exterior and interiorjoint . The figure showing t hat t he rigidity of t he specimens almo st doesn’t degenerate when t he initialcrack appear s in t he core , and a turning point can be found at t he curve but it isn’t very obvious. Wit ht he crack developing , an obvious t urning point can be found at t he curve , and at t his time , t he speci2men yields. Then t he load can increase f urt her , but it can’t increase too much f rom yielding load to ultimate load. When t he concrete at t he core collap ses and the plastic hinge occured at t he beamend ,t he load begins to decrease rat her t han increase.The ductility coefficient of two kinds of joint s is basically more than 3 (except for J 3 - 9) . But it should be noted t hat the design of specimens is based on the principle of joint core failure. The ratio of reinforcement of beam and column tends to be lower t han practical project s. If t he ratio is larger , t he failure of joint is probably prior to t hat of beam and column , so t he hysteretic curve reflect s t he ductil ity property of joint core.Joint experiment should be a subst ruct ure test (or a test of composite body of beams and col2 umns) . So t he load2displacement curves at t he beam end should be a general reflection of t he joint be2havior work as a subst ruct ure. Providing t hat the joint core fails af ter t he yield of beam and column (especially for beam) , t he load2displacement curves at t he beam end is plump , so the principle of “st rong col umn and weak beam , st ron ger j oi nt" should be ensured which conforms to t he seismic re2sistant principle.The experiment shows t hat t he stiff ness of joint core is large. Before the joint reaches ultimatestage , t he stiff ness of joint core decreases a little and the irrecoverable residual deformation is very small under alternate loading. When joint core enter s failure stage , t he shear deformation increases sharply , and t he stiff ness of joint core decreases obviously , and t he hysteretic curve appears shrink2 age , which is because of t he cohesive slip of beam reinforcement .3. 4 Influential Factors of Abnormal Joint Shear CapacityThe fir st factor is axial compression. Axial compression can enlarge t he compression area of col2 umn , and increase t he concrete compression area of joint core[124 ] . At t he same time , more shearst ransferred f rom beam steel to t he edge of joint core concrete will add to t he diagonal compression bar ,which decreases t he edge shear t hat leads to the crack of joint core concrete. So t he existence of axial comp ression cont ributes to imp roving t he capacity of initial cracks at joint core.The effect of axial compression on t horough cracking load and ultimate load isn’t very obvious[1 ] . The reason is t hat cont rasting wit h no axial compression , the accumulated damage effect of joint coreunder rever sed loading wit h axial compression is larger . Alt hough axial compression can improve t heshear st rengt h of concrete , it increases accumulated damage effect which leads to a decrease of the ad2vantage of axial compression. Therefore t he effect of axial compression on t horough cracking loadandultimate load is not very obvious.Hence , considering the lack of test data of abnormal joint , t he shear capacity formula of abnormal joint adopt 0. 05 nf c b j h j to calculate the effect of axial compression , which is based on the result s of t his experiment and referenced to t he experimental st udy and statistical analysis of Meinheit and J irsa ,et [5 ] .The second factor is horizontal stirrup . Horizontal stirrup has no effect on t he initial crackingshear of abnormal joint , while greatly improves t he t horough cracking shear . Af ter crack appeared , t he stirrup begins to resist t he shear and confines t he expansion of concrete[ 6 ] . This experiment showst hat t he st ress of stirrup s in each layer is not equal . When the joint fail s , t he stirrup s don’t yield simultaneous. Fig. 10 shows t he change of st ress dist ribution of stirrup s along core height wit h t he loadincreasing. Through analyzing test result s , it can be known t hat 80 percent of the height at the joint core can yield.The last factor is the change of sec2tion size of t he beam and column. Thesection change decreases t he initial crack2ing load about 30 p resent of abnormaljoint and makes t he initial crack appear att he position of joint mi nor core. The rea2son for t his p henomenon is t hat small up2per column section makes t he confinementof mi nor core concrete decrease and t heedge shear increase. But t he section change has lit tle effect on thorough cracking load. Af ter t horoughcracking , the joint enter s ultimate state while the external load can’t increase too much , which is dif2 ferent f rom t he behavior of abnormal joint t hat can carry much shear af ter thorough cracking.3. 5 Shear force formula of abnormal jointAs a part of f rame , t he design of joint shall meet t he requirement s of the f rame st ruct ure design , namely , t he joint design should not damage t he basic performance of t he st ruct ure.According to the principle of st ronger j oi nt , it is necessary for joint to have some safety reserva2 tion. The raised cost for conservational estimation of t he joint bearing capacity is small . But t he con2 servational estimation is very important to t he safety of the f rame st ruct ure. At t horough cracking stage , t he widt h of most cracks is more t han 0. 2 mm , which is bigger than t he suggested limit value in t he concrete design code. Big cracks will influence t he durability of st ruct ure. Hence , the bearing capacity at t horough cracking stage is applied to calculating t he bearing capacity of joint . According to t he analysis of t he working mechanisms of abnormal joint , it could be concludedt hat t he bearing capacity of joint core mainly depends on mi nor core when t he force t ransferred f rommaj or core to mi nor core. All kinds of working mechanisms are suitable to mi nor core element . Thus , a formula for calculating t he shear capacity of abnormal joint can be obtained based on Eq. 1. According to the above analysis of influential factor s of shear capacity of abnormal joint , and ref2 erence to Eq. 1 , a formula for calculating t he shear capacity of reinforced concrete f rame abnormal jointis suggested as followsV j = 0. 1ηjξ1 f c b j h j + 0. 1ηj nξ2 f c b j h j +ξ3 f yv A svj h0 - a′s s(2)Where h0 = effective dept h of small beam section in abnormal joint ;ξ1 = influential coefficient consider2ing mi nor core on working as cont rol element for calculating ;ξ2 = influential coefficient considering effect of axial compression ratio , it s value is 0. 5 , andξ3 = influential coefficient considering t hestir2rup doesn’t yield simultaneous , it s value is 0. 8 , n = N/ f c b c h j .From Fig. 8 , the shear capacity of abnormal joint depends on mi nor core , while maj or core has re2st rictive effect on mi nor core. The effect is related to t he ratio of maj or core area to mi nor core area , so assumingξ1 =αA d A x (3)Where A d = area of abnormal joint maj or core , choosing it as t he value of t he dept h of big beam multiplying t he height of lower column ; A x = area of abnormal joint mi nor core , choosing it as t he value oft he depth of small beam multiplying the height of upper column ; andα= parameter to be defined , it s value is 0. 8 derived f rom t he result s of t he experiment ( see Tab. 4)Then Eq. 2 can be replaced byV j = 0. 1ηjαA d A x f c b j h j + 0. 05ηj n f c b j h j + 0. 8 f yv h0 - a′s s(4)4 ConclusionsThe following conclusions can be drawn f rom t his study.(1) The seismic behavior of abnormal joint in reinforced concrete f rame st ruct ure is poor . Af tert horough cracking , t he joint enter s ultimate state while the external load can’t increase too much , andt he safety reservation of joint isn’t sufficient .(2) The characteristic of bearing load of minor core is similar to that of normal joint , but t he area bearing load is different . The shear capacity depend on t he size , t he st rengt h of concrete and the rein2forcement of mi nor core in abnormal joint . The maj or core has rest rictive effect on mi nor core. (3) Joint experiment should be a subst ruct ure test or a test of composite body of beams and col2 umns. Therefore t he load2displacement curves of t he beam end should be a general reflection of t he joint behavior working as a subst ruct ure. Studies of t he hysteretic curve of subst ruct ure should be based on t he whole st ructure. It is critical to guarantee t he stiff ness and st rengt h of joint core in prac2tice.(4) The formula of shear capacity for abnormal joint in reinforced concrete f rame is provided.References[1 ] TAN GJ iu2ru . The seismic behavior of steel reinforced concrete f rame [M] . Nanjing :Dongnan University Press ,1989 :1572163.[2 ] The research group of reinforcement concrete f rame joint . Shear capacity research of reinforced concrete f rame jointon reversed2cyclic loading[J ] . Journal of Building St ructures , 1983 , (6) :9215.[3 ] PAULA Y T ,PARK R. Joint s reinforced concrete f rames designed for earthquake resistance[ R] . New Zealand :De2partment of civil Engineering , University of Canterbury , Christchurch , 1984.[4 ] FU Jian2ping. Seismic behavior research of reinforced concrete f rame joint with the consideration of axialforce[J ] .Journal of Chongqing Univ , 2000 , (5) :23227.[5 ] MEINHEIT D F ,J IRSA J O. Shear st rength of R/ C beam2column connections [J ] . ACI St ructural Journal , 1993 ,(3) :61271.[6 ] KITA YAMA K, OTANI S ,AO YAMA H. Development of design criteria for RC interior beam2column joints ,de2sign of beam2column joint s for seismic resistance[ R] . SP123 ,ACI ,Det roit , 1991 :61272.[7 ] GB5001122001 ,Code for seismic design of buildings [ S] . Beijing : China Architectural and BuildingPress ,2001.钢筋混凝土框架异型节点抗震性能试验研究摘要：基于8个钢筋混凝土框架异型节点的试验研究，分析了异型框架节点的受力与常规框架节点的异同。
土木工程类英文专业词汇
土木工程类英文专业词汇土木工程是一个涉及土地开发、设计、建造和维护的复杂领域。
在这个领域中，有许多具有专业性、特定含义和用途的英文术语。
掌握这些专业词汇对于在这个领域工作或学习的人来说非常必要。
本文将介绍土木工程常用的英语专业词汇。
1.Civil engineering –土木工程学Civil engineering is a discipline that deals with the design, construction, and maintenance of the built environment, including buildings, roads, bridges, and other infrastructure.2.Architecture –建筑学Architecture is the art and science of designing and building structures, such as buildings and bridges.3.Planning –规划Planning is the process of making a detailed plan or layout for a project, including determining what resources will be needed to complete the project.4.Surveying –测量Surveying is the process of measuring and mapping the surface of the Earth, including land, water bodies, and buildings.5.Structural engineering –结构工程Structural engineering is a sub-discipline of civil engineering that deals with the design and analysis of structures, such as buildings, bridges, and other infrastructure.6.Geotechnical engineering –岩土工程Geotechnical engineering is a sub-discipline of civil engineering that deals with the study of soil and rock mechanics, and the design and construction of structures that are built on or in the ground.7.Transportation engineering –交通运输工程Transportation engineering is a sub-discipline of civil engineering that dealswith the design and construction of transportation infrastructure, such as roads, highways, and airports.8.Hydrology –水文学Hydrology is the study of water and its movement on the surface of the Earth, including precipitation, streams, rivers, and groundwater.9.Water resources engineering –水资源工程Water resources engineering is a sub-discipline of civil engineering that deals with the study of water resources and the design and construction of structures that manage and distribute water, including dams, reservoirs, and water treatment plants.10.Environmental engineering –环境工程Environmental engineering is a sub-discipline of civil engineering that deals with the study of environmental engineering principles and the design and construction of structures that protect the environment, such as water treatment plants and wastewater treatment plants.11.Construction –建造Construction refers to the process of building structures from design plans and specifications.12.Industrial engineering –工业工程Industrial engineering is a discipline that deals with the optimization of complex processes, systems, and organizations, with the goal of improving efficiency, productivity, and safety.13.Quantity surveying –工程测量Quantity surveying is the process of determining the quantity, cost, and value of materials needed to complete a construction project.14.Building –建筑物Building refers to a structure that is built for a specific purpose, such as a house, office building, or factory.15.Foundation –基础Foundation refers to the part of a structure that is in direct contact with the ground and supports the weight of the structure.16.Reinforcement –钢筋加固Reinforcement refers to the process of adding materials, such as steel bars, to strengthen a structure.17.Retaining wall –挡土墙A retaining wall is a structure that is built to support soil and prevent it from sliding down a slope.18.Roadway –道路A roadway is a paved surface that is designed for vehicles and pedestrians to travel on.19.Bridge –桥梁A bridge is a structure that is built to span a physical obstacle, such as a river or gorge, and provide a safe means of transportation.20.Culvert –排水管A culvert is a structure that is built to allow water to pass under a roadway or other structure.21.Dam –水坝A dam is a structure that is built to control the flow of water and to provide water for human consumption, irrigation, and hydroelectric power.22.Pile –桩A pile is a foundation support structure that is driven into the ground to supporta structure.23.Slab –地板A slab is a flat, horizontal surface that is used as a flooring material or to supporta structure.24.Tunnel –隧道A tunnel is an underground structure that is built for transportation, utilities, or other purposes.25.Asphalt –沥青Asphalt is a sticky, black, and highly viscous liquid that is used as a binder for paving materials.以上就是土木工程类英文专业词汇的介绍，这些专业词汇对于在土木工程领域中工作或学习的人来说都是非常重要的。
土木工程外文翻译经典
Design, Construction & Structural Details of Burj DubaiThe goal of the Burj Dubai Tower is not simply to be the world's highest building: it's to embody the world's highest aspirations. The superstructure is currently under construction and as of fall 2007 has reached over 160 stories. The final height of the building is 2,717 feet (828 meters). The height of the multi-use skyscraper will "comfortably" exceed the current record holder, the 509 meter (1671 ft) tall Taipei 101. The 280,000 m2(3,000,000 ft2) reinforced concrete multi-use Burj Dubai tower is utilized for retail, a Giorgio Armani Hotel, residential and office. As with all super-tall projects, difficult structural engineering problems needed to be addressed and resolved。
Structural System DescriptionBurj Khalifa has "refuge floors" at 25 to 30 story intervals that are more fire resistant and have separate air supplies in case of emergency. Its reinforced concrete structure makes it stronger than steel-frame skyscrapersDesigners purposely shaped the structural concrete Burj Dubai - "Y" shaped in plan - to reduce the wind forces on the tower, as well as to keep the structure simple and foster constructibility. The structural system can be described as a "buttressed" core (Figures 1, 2 and 3). Each wing, with its own high performance concrete corridor walls and perimeter columns, buttresses the others via a six-sided central core, or hexagonal hub. The result is a tower that is extremely stiff laterally and torsionally. SOM applied a rigorous geometry to the tower that aligned all the common central core, wall, and column elements。
(完整版)土木工程毕业设计外文文献翻译
外文文献翻译Reinforced ConcreteConcrete and reinforced concrete are used as building materials in every country. In many, including the United States and Canada, reinforced concrete is a dominant structural material in engineered construction. The universal nature of reinforced concrete construction stems from the wide availability of reinforcing bars and the constituents of concrete, gravel, sand, and cement, the relatively simple skills required in concrete construction, and the economy of reinforced concrete compared to other forms of construction. Concrete and reinforced concrete are used in bridges, buildings of all sorts underground structures, water tanks, television towers, offshore oil exploration and production structures, dams, and even in ships.Reinforced concrete structures may be cast-in-place concrete, constructed in their final location, or they may be precast concrete produced in a factory and erected at the construction site. Concrete structures may be severe and functional in design, or the shape and layout and be whimsical and artistic. Few other building materials off the architect and engineer such versatility and scope.Concrete is strong in compression but weak in tension. As a result, cracks develop whenever loads, or restrained shrinkage of temperature changes, give rise to tensile stresses in excess of the tensile strength of the concrete. In a plain concrete beam, the moments about the neutral axis due to applied loads are resisted by an internal tension-compression couple involving tension in the concrete. Such a beam fails very suddenly and completely when the first crack forms. In a reinforced concrete beam, steel bars are embedded in the concrete in such a way that the tension forces needed for moment equilibrium after the concrete cracks can be developed in the bars.The construction of a reinforced concrete member involves building a from of mold in the shape of the member being built. The form must be strong enough to support both the weight and hydrostatic pressure of the wet concrete, and any forces applied to it by workers, concrete buggies, wind, and so on. The reinforcement is placed in this form and held in placeduring the concreting operation. After the concrete has hardened, the forms are removed. As the forms are removed, props of shores are installed to support the weight of the concrete until it has reached sufficient strength to support the loads by itself.The designer must proportion a concrete member for adequate strength to resist the loads and adequate stiffness to prevent excessive deflections. In beam must be proportioned so that it can be constructed. For example, the reinforcement must be detailed so that it can be assembled in the field, and since the concrete is placed in the form after the reinforcement is in place, the concrete must be able to flow around, between, and past the reinforcement to fill all parts of the form completely.The choice of whether a structure should be built of concrete, steel, masonry, or timber depends on the availability of materials and on a number of value decisions. The choice of structural system is made by the architect of engineer early in the design, based on the following considerations:1. Economy. Frequently, the foremost consideration is the overall const of the structure. This is, of course, a function of the costs of the materials and the labor necessary to erect them. Frequently, however, the overall cost is affected as much or more by the overall construction time since the contractor and owner must borrow or otherwise allocate money to carry out the construction and will not receive a return on this investment until the building is ready for occupancy. In a typical large apartment of commercial project, the cost of construction financing will be a significant fraction of the total cost. As a result, financial savings due to rapid construction may more than offset increased material costs. For this reason, any measures the designer can take to standardize the design and forming will generally pay off in reduced overall costs.In many cases the long-term economy of the structure may be more important than the first cost. As a result, maintenance and durability are important consideration.2. Suitability of material for architectural and structural function.A reinforced concrete system frequently allows the designer to combine the architectural and structural functions. Concrete has the advantage that it is placed in a plastic condition and is given the desired shapeand texture by means of the forms and the finishing techniques. This allows such elements ad flat plates or other types of slabs to serve as load-bearing elements while providing the finished floor and / or ceiling surfaces. Similarly, reinforced concrete walls can provide architecturally attractive surfaces in addition to having the ability to resist gravity, wind, or seismic loads. Finally, the choice of size of shape is governed by the designer and not by the availability of standard manufactured members.3. Fire resistance. The structure in a building must withstand the effects of a fire and remain standing while the building is evacuated and the fire is extinguished. A concrete building inherently has a 1- to 3-hour fire rating without special fireproofing or other details. Structural steel or timber buildings must be fireproofed to attain similar fire ratings.4. Low maintenance.Concrete members inherently require less maintenance than do structural steel or timber members. This is particularly true if dense, air-entrained concrete has been used for surfaces exposed to the atmosphere, and if care has been taken in the design to provide adequate drainage off and away from the structure. Special precautions must be taken for concrete exposed to salts such as deicing chemicals.5. Availability of materials. Sand, gravel, cement, and concrete mixing facilities are very widely available, and reinforcing steel can be transported to most job sites more easily than can structural steel. As a result, reinforced concrete is frequently used in remote areas.On the other hand, there are a number of factors that may cause one to select a material other than reinforced concrete. These include:1. Low tensile strength.The tensile strength concrete is much lower than its compressive strength ( about 1/10 ), and hence concrete is subject to cracking. In structural uses this is overcome by using reinforcement to carry tensile forces and limit crack widths to within acceptable values. Unless care is taken in design and construction, however, these cracks may be unsightly or may allow penetration of water. When this occurs, water or chemicals such as road deicing salts may cause deterioration or staining of the concrete. Special design details are required in such cases. In the case of water-retaining structures, special details and /of prestressing are required to prevent leakage.2. Forms and shoring. The construction of a cast-in-place structure involves three steps not encountered in the construction of steel or timber structures. These are ( a ) the construction of the forms, ( b ) the removal of these forms, and (c) propping or shoring the new concrete to support its weight until its strength is adequate. Each of these steps involves labor and / or materials, which are not necessary with other forms of construction.3. Relatively low strength per unit of weight for volume.The compressive strength of concrete is roughly 5 to 10% that of steel, while its unit density is roughly 30% that of steel. As a result, a concrete structure requires a larger volume and a greater weight of material than does a comparable steel structure. As a result, long-span structures are often built from steel.4. Time-dependent volume changes. Both concrete and steel undergo-approximately the same amount of thermal expansion and contraction. Because there is less mass of steel to be heated or cooled, and because steel is a better concrete, a steel structure is generally affected by temperature changes to a greater extent than is a concrete structure. On the other hand, concrete undergoes frying shrinkage, which, if restrained, may cause deflections or cracking. Furthermore, deflections will tend to increase with time, possibly doubling, due to creep of the concrete under sustained loads.In almost every branch of civil engineering and architecture extensive use is made of reinforced concrete for structures and foundations. Engineers and architects requires basic knowledge of reinforced concrete design throughout their professional careers. Much of this text is directly concerned with the behavior and proportioning of components that make up typical reinforced concrete structures-beams, columns, and slabs. Once the behavior of these individual elements is understood, the designer will have the background to analyze and design a wide range of complex structures, such as foundations, buildings, and bridges, composed of these elements.Since reinforced concrete is a no homogeneous material that creeps, shrinks, and cracks, its stresses cannot be accurately predicted by the traditional equations derived in a course in strength of materials forhomogeneous elastic materials. Much of reinforced concrete design in therefore empirical, i.e., design equations and design methods are based on experimental and time-proved results instead of being derived exclusively from theoretical formulations.A thorough understanding of the behavior of reinforced concrete will allow the designer to convert an otherwise brittle material into tough ductile structural elements and thereby take advantage of concrete’s desirable characteristics, its high compressive strength, its fire resistance, and its durability.Concrete, a stone like material, is made by mixing cement, water, fine aggregate ( often sand ), coarse aggregate, and frequently other additives ( that modify properties ) into a workable mixture. In its unhardened or plastic state, concrete can be placed in forms to produce a large variety of structural elements. Although the hardened concrete by itself, i.e., without any reinforcement, is strong in compression, it lacks tensile strength and therefore cracks easily. Because unreinforced concrete is brittle, it cannot undergo large deformations under load and fails suddenly-without warning. The addition fo steel reinforcement to the concrete reduces the negative effects of its two principal inherent weaknesses, its susceptibility to cracking and its brittleness. When the reinforcement is strongly bonded to the concrete, a strong, stiff, and ductile construction material is produced. This material, called reinforced concrete, is used extensively to construct foundations, structural frames, storage takes, shell roofs, highways, walls, dams, canals, and innumerable other structures and building products. Two other characteristics of concrete that are present even when concrete is reinforced are shrinkage and creep, but the negative effects of these properties can be mitigated by careful design.A code is a set technical specifications and standards that control important details of design and construction. The purpose of codes it produce structures so that the public will be protected from poor of inadequate and construction.Two types f coeds exist. One type, called a structural code, is originated and controlled by specialists who are concerned with the proper use of a specific material or who are involved with the safe design of a particular class of structures.The second type of code, called a building code, is established to cover construction in a given region, often a city or a state. The objective of a building code is also to protect the public by accounting for the influence of the local environmental conditions on construction. For example, local authorities may specify additional provisions to account for such regional conditions as earthquake, heavy snow, or tornados. National structural codes genrally are incorporated into local building codes.The American Concrete Institute ( ACI ) Building Code covering the design of reinforced concrete buildings. It contains provisions covering all aspects of reinforced concrete manufacture, design, and construction. It includes specifications on quality of materials, details on mixing and placing concrete, design assumptions for the analysis of continuous structures, and equations for proportioning members for design forces.All structures must be proportioned so they will not fail or deform excessively under any possible condition of service. Therefore it is important that an engineer use great care in anticipating all the probable loads to which a structure will be subjected during its lifetime.Although the design of most members is controlled typically by dead and live load acting simultaneously, consideration must also be given to the forces produced by wind, impact, shrinkage, temperature change, creep and support settlements, earthquake, and so forth.The load associated with the weight of the structure itself and its permanent components is called the dead load. The dead load of concrete members, which is substantial, should never be neglected in design computations. The exact magnitude of the dead load is not known accurately until members have been sized. Since some figure for the dead load must be used in computations to size the members, its magnitude must be estimated at first. After a structure has been analyzed, the members sized, and architectural details completed, the dead load can be computed more accurately. If the computed dead load is approximately equal to the initial estimate of its value ( or slightly less ), the design is complete, but if a significant difference exists between the computed and estimated values of dead weight, the computations should be revised using an improved value of dead load. An accurate estimate of dead load is particularly important when spans are long, say over 75 ft ( 22.9 m ),because dead load constitutes a major portion of the design load.Live loads associated with building use are specific items of equipment and occupants in a certain area of a building, building codes specify values of uniform live for which members are to be designed.After the structure has been sized for vertical load, it is checked for wind in combination with dead and live load as specified in the code. Wind loads do not usually control the size of members in building less than 16 to 18 stories, but for tall buildings wind loads become significant and cause large forces to develop in the structures. Under these conditions economy can be achieved only by selecting a structural system that is able to transfer horizontal loads into the ground efficiently.钢筋混凝土在每一个国家，混凝土及钢筋混凝土都被用来作为建筑材料。
土木工程外文文献及翻译
本科毕业设计外文文献及译文文献、资料题目：Designing Against Fire Of Building 文献、资料来源：国道数据库文献、资料发表（出版）日期：2008.3.25院（部）：土木工程学院专业：土木工程班级：土木辅修091姓名：xxxx外文文献:Designing Against Fire Of BulidingxxxABSTRACT:This paper considers the design of buildings for fire safety. It is found that fire and the associ- ated effects on buildings is significantly different to other forms of loading such as gravity live loads, wind and earthquakes and their respective effects on the building structure. Fire events are derived from the human activities within buildings or from the malfunction of mechanical and electrical equipment provided within buildings to achieve a serviceable environment. It is therefore possible to directly influence the rate of fire starts within buildings by changing human behaviour, improved maintenance and improved design of mechanical and electrical systems. Furthermore, should a fire develops, it is possible to directly influence the resulting fire severity by the incorporation of fire safety systems such as sprinklers and to provide measures within the building to enable safer egress from the building. The ability to influence the rate of fire starts and the resulting fire severity is unique to the consideration of fire within buildings since other loads such as wind and earthquakes are directly a function of nature. The possible approaches for designing a building for fire safety are presented using an example of a multi-storey building constructed over a railway line. The design of both the transfer structure supporting the building over the railway and the levels above the transfer structure are considered in the context of current regulatory requirements. The principles and assumptions associ- ated with various approaches are discussed.1 INTRODUCTIONOther papers presented in this series consider the design of buildings for gravity loads, wind and earthquakes.The design of buildings against such load effects is to a large extent covered by engineering based standards referenced by the building regulations. This is not the case, to nearly the same extent, in the case of fire. Rather, it is building regulations such as the Building Code of Australia (BCA) that directly specify most of the requirements for fire safety of buildings with reference being made to Standards such as AS3600 or AS4100 for methods for determining the fire resistance of structural elements.The purpose of this paper is to consider the design of buildings for fire safety from an engineering perspective (as is currently done for other loads such as wind or earthquakes), whilst at the same time,putting such approaches in the context of the current regulatory requirements.At the outset,it needs to be noted that designing a building for fire safety is far morethan simply considering the building structure and whether it has sufficient structural adequacy.This is because fires can have a direct influence on occupants via smoke and heat and can grow in size and severity unlike other effects imposed on the building. Notwithstanding these comments, the focus of this paper will be largely on design issues associated with the building structure.Two situations associated with a building are used for the purpose of discussion. The multi-storey office building shown in Figure 1 is supported by a transfer structure that spans over a set of railway tracks. It is assumed that a wide range of rail traffic utilises these tracks including freight and diesel locomotives. The first situation to be considered from a fire safety perspective is the transfer structure.This is termed Situation 1 and the key questions are: what level of fire resistance is required for this transfer structure and how can this be determined? This situation has been chosen since it clearly falls outside the normal regulatory scope of most build- ing regulations. An engineering solution, rather than a prescriptive one is required. The second fire situation (termed Situation 2) corresponds to a fire within the office levels of the building and is covered by building regulations. This situation is chosen because it will enable a discussion of engineering approaches and how these interface with the building regulations–since both engineering and prescriptive solutions are possible.2 UNIQUENESS OF FIRE2.1 IntroductionWind and earthquakes can be considered to b e “natural” phenomena over which designers have no control except perhaps to choose the location of buildings more carefully on the basis of historical records and to design building to resist sufficiently high loads or accelerations for the particular location. Dead and live loads in buildings are the result of gravity. All of these loads are variable and it is possible (although generally unlikely) that the loads may exceed the resistance of the critical structural members resulting in structural failure.The nature and influence of fires in buildings are quite different to those associated with other“loads” to which a building may be subjected to. The essential differences are described in the following sections.2.2 Origin of FireIn most situations (ignoring bush fires), fire originates from human activities within the building or the malfunction of equipment placed within the building to provide a serviceable environment. It follows therefore that it is possible to influence the rate of fire starts by influencing human behaviour, limiting and monitoring human behaviour and improving thedesign of equipment and its maintenance. This is not the case for the usual loads applied to a building.2.3 Ability to InfluenceSince wind and earthquake are directly functions of nature, it is not possible to influence such events to any extent. One has to anticipate them and design accordingly. It may be possible to influence the level of live load in a building by conducting audits and placing restrictions on contents. However, in the case of a fire start, there are many factors that can be brought to bear to influence the ultimate size of the fire and its effect within the building. It is known that occupants within a building will often detect a fire and deal with it before it reaches a sig- nificant size. It is estimated that less than one fire in five (Favre, 1996) results in a call to the fire brigade and for fires reported to the fire brigade, the majority will be limited to the room of fire origin. In oc- cupied spaces, olfactory cues (smell) provide powerful evidence of the presence of even a small fire. The addition of a functional smoke detection system will further improve the likelihood of detection and of action being taken by the occupants.Fire fighting equipment, such as extinguishers and hose reels, is generally provided within buildings for the use of occupants and many organisations provide training for staff in respect of the use of such equipment.The growth of a fire can also be limited by automatic extinguishing systems such as sprinklers, which can be designed to have high levels of effectiveness.Fires can also be limited by the fire brigade depending on the size and location of the fire at the time of arrival. 2.4 Effects of FireThe structural elements in the vicinity of the fire will experience the effects of heat. The temperatures within the structural elements will increase with time of exposure to the fire, the rate of temperature rise being dictated by the thermal resistance of the structural element and the severity of the fire. The increase in temperatures within a member will result in both thermal expansion and,eventually,a reduction in the structural resistance of the member. Differential thermal expansion will lead to bowing of a member. Significant axial expansion will be accommodated in steel members by either overall or local buckling or yielding of local- ised regions. These effects will be detrimental for columns but for beams forming part of a floor system may assist in the development of other load resisting mechanisms (see Section 4.3.5).With the exception of the development of forces due to restraint of thermal expansion, fire does not impose loads on the structure but rather reduces stiffness and strength. Such effects are not instantaneous but are a function of time and this is different to the effects of loads such as earthquake and wind that are more or less instantaneous.Heating effects associated with a fire will not be significant or the rate of loss of capacity will be slowed if:(a) the fire is extinguished (e.g. an effective sprinkler system)(b) the fire is of insufficient severity – insufficient fuel, and/or(c)the structural elements have sufficient thermal mass and/or insulation to slow the rise in internal temperatureFire protection measures such as providing sufficient axis distance and dimensions for concrete elements, and sufficient insulation thickness for steel elements are examples of (c). These are illustrated in Figure 2.The two situations described in the introduction are now considered.3 FIRE WITHIN BUILDINGS3.1 Fire Safety ConsiderationsThe implications of fire within the occupied parts of the office building (Figure 1) (Situation 2) are now considered. Fire statistics for office buildings show that about one fatality is expected in an office building for every 1000 fires reported to the fire brigade. This is an order of magnitude less than the fatality rate associated with apartment buildings. More than two thirds of fires occur during occupied hours and this is due to the greater human activity and the greater use of services within the building. It is twice as likely that a fire that commences out of normal working hours will extend beyond the enclosure of fire origin.A relatively small fire can generate large quantities of smoke within the floor of fire origin. If the floor is of open-plan construction with few partitions, the presence of a fire during normal occupied hours is almost certain to be detected through the observation of smoke on the floor. The presence of full height partitions across the floor will slow the spread of smoke and possibly also the speed at which the occupants detect the fire. Any measures aimed at improving housekeeping, fire awareness and fire response will be beneficial in reducing thelikelihood of major fires during occupied hours.For multi-storey buildings, smoke detection systems and alarms are often provided to give “automatic” detection and warning to the occupants. An alarm signal is also transmitted to the fire brigade.Should the fire not be able to be controlled by the occupants on the fire floor, they will need to leave the floor of fire origin via the stairs. Stair enclosures may be designed to be fire-resistant but this may not be sufficient to keep the smoke out of the stairs. Many buildings incorporate stair pressurisation systems whereby positive airflow is introduced into the stairs upon detection of smoke within the building. However, this increases the forces required to open the stair doors and makes it increasingly difficult to access the stairs. It is quite likely that excessive door opening forces will exist(Fazio et al,2006)From a fire perspective, it is common to consider that a building consists of enclosures formed by the presence of walls and floors.An enclosure that has sufficiently fire-resistant boundaries (i.e. walls and floors) is considered to constitute a fire compartment and to be capable of limiting the spread of fire to an adjacent compartment. However, the ability of such boundaries to restrict the spread of fire can be severely limited by the need to provide natural lighting (windows)and access openings between the adjacent compartments (doors and stairs). Fire spread via the external openings (windows) is a distinct possibility given a fully developed fire. Limit- ing the window sizes and geometry can reduce but not eliminate the possibility of vertical fire spread.By far the most effective measure in limiting fire spread, other than the presence of occupants, is an effective sprinkler system that delivers water to a growing fire rapidly reducing the heat being generated and virtually extinguishing it.3.2 Estimating Fire SeverityIn the absence of measures to extinguish developing fires, or should such systems fail; severe fires can develop within buildings.In fire en gineering literature, the term “fire load” refers to the quantity of combustibles within an enclosure and not the loads (forces) applied to the structure during a fire. Similarly, fire load density refers to the quantity of fuel per unit area. It is normally expressed in terms of MJ/m2 or kg/m2 of wood equivalent. Surveys of combustibles for various occupancies (i.e offices, retail, hospitals, warehouses, etc)have been undertaken and a good summary of the available data is given in FCRC (1999). As would be expected, the fire load density is highly variable. Publications such as the International Fire Engineering Guidelines (2005) give fire load data in terms of the mean and 80th percentile.The latter level of fire load density is sometimes taken asthe characteristic fire load density and is sometimes taken as being distributed according to a Gumbel distribution (Schleich et al, 1999).The rate at which heat is released within an enclosure is termed the heat release rate (HRR) and normally expressed in megawatts (MW). The application of sufficient heat to a combustible material results in the generation of gases some of which are combustible. This process is called pyrolisation.Upon coming into contact with sufficient oxygen these gases ignite generating heat. The rate of burning(and therefore of heat generation) is therefore dependent on the flow of air to the gases generated by the pyrolising fuel.This flow is influenced by the shape of the enclosure (aspect ratio), and the position and size of any potential openings. It is found from experiments with single openings in approximately cubic enclosures that the rate of burning is directly proportional to A h where A is the area of the opening and h is the opening height. It is known that for deep enclosures with single openings that burning will occur initially closest to the opening moving back into the enclosure once the fuel closest to the opening is consumed (Thomas et al, 2005). Significant temperature variations throughout such enclosures can be expected.The use of the word ‘opening’ in relation to real building enclosures refers to any openings present around the walls including doors that are left open and any windows containing non fire-resistant glass.It is presumed that such glass breaks in the event of development of a significant fire. If the windows could be prevented from breaking and other sources of air to the enclosure limited, then the fire would be prevented from becoming a severe fire.Various methods have been developed for determining the potential severity of a fire within an enclosure.These are described in SFPE (2004). The predictions of these methods are variable and are mostly based on estimating a representative heat release rate (HRR) and the proportion of total fuel ςlikely to be consumed during the primary burning stage (Figure 4). Further studies of enclosure fires are required to assist with the development of improved models, as the behaviour is very complex.3.3 Role of the Building StructureIf the design objectives are to provide an adequate level of safety for the occupants and protection of adjacent properties from damage, then the structural adequacy of the building in fire need only be sufficient to allow the occupants to exit the building and for the building to ultimately deform in a way that does not lead to damage or fire spread to a building located on an adjacent site.These objectives are those associated with most building regulations includingthe Building Code of Australia (BCA). There could be other objectives including protection of the building against significant damage. In considering these various objectives, the following should be taken into account when considering the fire resistance of the building structure.3.3.1 Non-Structural ConsequencesSince fire can produce smoke and flame, it is important to ask whether these outcomes will threaten life safety within other parts of the building before the building is compromised by a loss of structural adequacy? Is search and rescue by the fire brigade not feasible given the likely extent of smoke? Will the loss of use of the building due to a severe fire result in major property and income loss? If the answer to these questions is in the affirmative, then it may be necessary to minimise the occurrence of a significant fire rather than simply assuming that the building structure needs to be designed for high levels of fire resistance. A low-rise shopping centre with levels interconnected by large voids is an example of such a situation.3.3.2 Other Fire Safety SystemsThe presence of other systems (e.g. sprinklers) within the building to minimise the occurrence of a serious fire can greatly reduce the need for the structural elements to have high levels of fire resistance. In this regard, the uncertainties of all fire-safety systems need to be considered. Irrespective of whether the fire safety system is the sprinkler system, stair pressurisation, compartmentation or the system giving the structure a fire-resistance level (e.g. concrete cover), there is an uncertainty of performance. Uncertainty data is available for sprinkler systems(because it is relatively easy to collect) but is not readily available for the other fire safety systems. This sometimes results in the designers and building regulators considering that only sprinkler systems are subject to uncertainty. In reality, it would appear that sprinklers systems have a high level of performance and can be designed to have very high levels of reliability.3.3.3 Height of BuildingIt takes longer for a tall building to be evacuated than a short building and therefore the structure of a tall building may need to have a higher level of fire resistance. The implications of collapse of tall buildings on adjacent properties are also greater than for buildings of only several storeys.3.3.4 Limited Extent of BurningIf the likely extent of burning is small in comparison with the plan area of the building, then the fire cannot have a significant impact on the overall stability of the building structure. Examples of situations where this is the case are open-deck carparks and very large area building such as shopping complexes where the fire-effected part is likely to be small in relation to area of the building floor plan.3.3.5 Behaviour of Floor ElementsThe effect of real fires on composite and concrete floors continues to be a subject of much research.Experimental testing at Cardington demonstrated that when parts of a composite floor are subject to heating, large displacement behaviour can develop that greatly assists the load carrying capacity of the floor beyond that which would predicted by considering only the behaviour of the beams and slabs in isolation.These situations have been analysed by both yield line methods that take into account the effects of membrane forces (Bailey, 2004) and finite element techniques. In essence, the methods illustrate that it is not necessary to insulate all structural steel elements in a composite floor to achieve high levels of fire resistance.This work also demonstrated that exposure of a composite floor having unprotected steel beams, to a localised fire, will not result in failure of the floor.A similar real fire test on a multistory reinforced concrete building demonstrated that the real structural behaviour in fire was significantly different to that expected using small displacement theory as for normal tempera- ture design (Bailey, 2002) with the performance being superior than that predicted by considering isolated member behaviour.3.4 Prescriptive Approach to DesignThe building regulations of most countries provide prescriptive requirements for the design of buildings for fire.These requirements are generally not subject to interpretation and compliance with them makes for simpler design approval–although not necessarily the most cost-effective designs.These provisions are often termed deemed-to-satisfy (DTS) provisions. All aspects of designing buildings for fire safety are covered–the provision of emergency exits, spacings between buildings, occupant fire fighting measures, detection and alarms, measures for automatic fire suppression, air and smoke handling requirements and last, but not least, requirements for compartmentation and fire resistance levels for structural members. However, there is little evidence that the requirements have been developed from a systematic evaluation of fire safety. Rather it would appear that many of the requirements have been added one to another to deal with another fire incident or to incorporate a new form of technology. There does not appear to have been any real attempt to determine which provision have the most significant influence on fire safety and whether some of the former provisions could be modified.The FRL requirements specified in the DTS provisions are traditionally considered to result in member resistances that will only rarely experience failure in the event of a fire.This is why it is acceptable to use the above arbitrary point in time load combination for assessing members in fire. There have been attempts to evaluate the various deemed-to-satisfy provisions (particularly the fire- resistance requirements)from a fire-engineering perspective taking intoaccount the possible variations in enclosure geometry, opening sizes and fire load (see FCRC, 1999).One of the outcomes of this evaluation was the recognition that deemed-to- satisfy provisions necessarily cover the broad range of buildings and thus must, on average, be quite onerous because of the magnitude of the above variations.It should be noted that the DTS provisions assume that compartmentation works and that fire is limited to a single compartment. This means that fire is normally only considered to exist at one level. Thus floors are assumed to be heated from below and columns only over one storey height.3.5 Performance-Based DesignAn approach that offers substantial benefits for individual buildings is the move towards performance-based regulations. This is permitted by regulations such as the BCA which state that a designer must demonstrate that the particular building will achieve the relevant performance requirements. The prescriptive provisions (i.e. the DTS provisions) are presumed to achieve these requirements. It is necessary to show that any building that does not conform to the DTS provisions will achieve the performance requirements.But what are the performance requirements? Most often the specified performance is simply a set of performance statements (such as with the Building Code of Australia)with no quantitative level given. Therefore, although these statements remind the designer of the key elements of design, they do not, in themselves, provide any measure against which to determine whether the design is adequately safe.Possible acceptance criteria are now considered.3.5.1 Acceptance CriteriaSome guidance as to the basis for acceptable designs is given in regulations such as the BCA. These and other possible bases are now considered in principle.(i)compare the levels of safety (with respect to achieving each of the design objectives) of the proposed alternative solution with those asso- ciated with a corresponding DTS solution for the building.This comparison may be done on either a qualitative or qualitative risk basis or perhaps a combination. In this case, the basis for comparison is an acceptable DTS solution. Such an approach requires a “holistic” approach to safety whereby all aspects relevant to safety, including the structure, are considered. This is, by far, the most common basis for acceptance.(ii)undertake a probabilistic risk assessment and show that the risk associated with the proposed design is less than that associated with common societal activities such as using pub lic transport. Undertaking a full probabilistic risk assessment can be very difficult for all but the simplest situations.Assuming that such an assessment is undertaken it will be necessary for the stakeholders to accept the nominated level of acceptable risk. Again, this requires a “holistic”approach to fire safety.(iii) a design is presented where it is demonstrated that all reasonable measures have been adopted to manage the risks and that any possible measures that have not been adopted will have negligible effect on the risk of not achieving the design objectives.(iv) as far as the building structure is concerned,benchmark the acceptable probability of failure in fire against that for normal temperature design. This is similar to the approach used when considering Building Situation 1 but only considers the building structure and not the effects of flame or smoke spread. It is not a holistic approach to fire safety.Finally, the questions of arson and terrorism must be considered. Deliberate acts of fire initiation range from relatively minor incidents to acts of mass destruction.Acts of arson are well within the accepted range of fire events experienced by build- ings(e.g. 8% of fire starts in offices are deemed "suspicious"). The simplest act is to use a small heat source to start a fire. The resulting fire will develop slowly in one location within the building and will most probably be controlled by the various fire- safety systems within the building. The outcome is likely to be the same even if an accelerant is used to assist fire spread.An important illustration of this occurred during the race riots in Los Angeles in 1992 (Hart 1992) when fires were started in many buildings often at multiple locations. In the case of buildings with sprinkler systems,the damage was limited and the fires significantly controlled.Although the intent was to destroy the buildings,the fire-safety systems were able to limit the resulting fires. Security measures are provided with systems such as sprinkler systems and include:- locking of valves- anti-tamper monitoring- location of valves in secure locationsFurthermore, access to significant buildings is often restricted by security measures.The very fact that the above steps have been taken demonstrates that acts of destruction within buildings are considered although most acts of arson do not involve any attempt to disable the fire-safety systems.At the one end of the spectrum is "simple" arson and at the other end, extremely rare acts where attempts are made to destroy the fire-safety systems along with substantial parts of the building.This can be only achieved through massive impact or the use of explosives. The latter may be achieved through explosives being introduced into the building or from outside by missile attack.The former could result from missile attack or from the collision of a large aircraft. The greater the destructiveness of the act,the greater the means and knowledge required. Conversely, the more extreme the act, the less confidence there can be in designing against suchan act. This is because the more extreme the event, the harder it is to predict precisely and the less understood will be its effects. The important point to recognise is that if sufficient means can be assembled, then it will always be possible to overcome a particular building design.Thus these acts are completely different to the other loadings to which a building is subjected such as wind,earthquake and gravity loading. This is because such acts of destruction are the work of intelligent beings and take into account the characteristics of the target.Should high-rise buildings be designed for given terrorist activities,then terrorists will simply use greater means to achieve the end result.For example, if buildings were designed to resist the impact effects from a certain size aircraft, then the use of a larger aircraft or more than one aircraft could still achieve destruction of the building. An appropriate strategy is therefore to minimise the likelihood of means of mass destruction getting into the hands of persons intent on such acts. This is not an engineering solution associated with the building structure.It should not be assumed that structural solutions are always the most appropriate, or indeed, possible.In the same way, aircrafts are not designed to survive a major fire or a crash landing but steps are taken to minimise the likelihood of either occurrence.The mobilization of large quantities of fire load (the normal combustibles on the floors) simultaneously on numerous levels throughout a building is well outside fire situations envisaged by current fire test standards and prescriptive regulations. Risk management measures to avoid such a possibility must be considered.4 CONCLUSIONSFire differs significantly from other “loads” such as wind, live load and earthquakes i n respect of its origin and its effects.Due to the fact that fire originates from human activities or equipment installed within buildings, it is possible to directly influence the potential effects on the building by reducing the rate of fire starts and providing measures to directly limit fire severity.The design of buildings for fire safety is mostly achieved by following the prescriptive requirements of building codes such as the BCA. For situations that fall outside of the scope of such regulations, or where proposed designs are not in accordance with the prescriptive requirements, it is possible to undertake performance-based fire engineering designs.However, there are no design codes or standards or detailed methodologies available for undertaking such designs.Building regulations require that such alternative designs satisfy performance requirements and give some guidance as to the basis for acceptance of these designs (i.e. acceptance criteria).This paper presents a number of possible acceptance criteria, all of which use the measure of risk level as the basis for comparison.Strictly, when considering the risks。
土木工程毕业论文中英文翻译
外文翻译班级：xxx学号：xxx姓名：xxx一、外文原文：Structural Systems to resist lateral loads Commonly Used structural SystemsWith loads measured in tens of thousands kips, there is little room in the design of high-rise buildings for excessively complex thoughts. Indeed, the better high-rise buildings carry the universal traits of simplicity of thought and clarity of expression.It does not follow that there is no room for grand thoughts. Indeed, it is with such grand thoughts that the new family of high-rise buildings has evolved. Perhaps more important, the new concepts of but a few years ago have become commonplace in today’ s technology.Omitting some concepts that are related strictly to the materials of construction, the most commonly used structural systems used in high-rise buildings can be categorized as follows:1.Moment-resisting frames.2.Braced frames, including eccentrically braced frames.3.Shear walls, including steel plate shear walls.4.Tube-in-tube structures.5.Core-interactive structures.6.Cellular or bundled-tube systems.Particularly with the recent trend toward more complex forms, but in response also to the need for increased stiffness to resist the forces from wind and earthquake, most high-rise buildings have structural systems built up of combinations of frames, braced bents, shear walls, and related systems. Further, for the taller buildings, the majorities are composed of interactive elements in three-dimensional arrays.The method of combining these elements is the very essence of the design process for high-rise buildings. These combinations need evolve in response to environmental, functional, and cost considerations so as to provide efficient structures that provoke the architectural development to new heights. This is not to say that imaginative structural design can create great architecture. To the contrary, many examples of fine architecture have been created with only moderate support from the structural engineer, while only fine structure, not great architecture, can be developed without the genius and the leadership of a talented architect. In any event, the best of both is needed to formulate a truly extraordinary design of a high-rise building.While comprehensive discussions of these seven systems are generally available in the literature, further discussion is warranted here .The essence of the design process is distributed throughout the discussion.Moment-Resisting FramesPerhaps the most commonly used system in low-to medium-rise buildings, the moment-resisting frame, is characterized by linear horizontal and vertical members connected essentially rigidly at their joints. Such frames are used as a stand-alone system or in combination with other systems so as to provide the needed resistance to horizontal loads. In the taller of high-rise buildings, the system is likely to be found inappropriate for a stand-alone system, this because of the difficulty in mobilizing sufficient stiffness under lateral forces.Analysis can be accomplished by STRESS, STRUDL, or a host of other appropriate computer programs; analysis by the so-called portal method of the cantilever method has no place in today’s technology.Because of the intrinsic flexibility of the column/girder intersection, and because preliminary designs should aim to highlight weaknesses of systems, it is not unusual to use center-to-center dimensions for the frame in the preliminary analysis. Of course, in the latter phases of design, a realistic appraisal in-joint deformation is essential.Braced Frame sThe braced frame, intrinsically stiffer than the moment –resisting frame, finds also greater application to higher-rise buildings. The system is characterized by linear horizontal, vertical, and diagonal members, connected simply or rigidly at their joints. It is used commonly inconjunction with other systems for taller buildings and as a stand-alone system in low-to medium-rise buildings.While the use of structural steel in braced frames is common, concrete frames are more likely to be of the larger-scale variety.Of special interest in areas of high seismicity is the use of the eccentric braced frame.Again, analysis can be by STRESS, STRUDL, or any one of a series of two –or three dimensional analysis computer programs. And again, center-to-center dimensions are used commonly in the preliminary analysis. Shear wallsThe shear wall is yet another step forward along a progression of ever-stiffer structural systems. The system is characterized by relatively thin, generally but not always concrete elements that provide both structural strength and separation between building functions.In high-rise buildings, shear wall systems tend to have a relatively high aspect ratio, that is, their height tends to be large compared to their width. Lacking tension in the foundation system, any structural element is limited in its ability to resist overturning moment by the width of the system and by the gravity load supported by the element. Limited to a narrow overturning, One obvious use of the system, which does have the needed width, is in the exterior walls of building, where the requirement for windows is kept small.Structural steel shear walls, generally stiffened against buckling by a concrete overlay, have found application where shear loads are high. The system, intrinsically more economical than steel bracing, is particularly effective in carrying shear loads down through the taller floors in the areas immediately above grade. The system has the further advantage of having high ductility a feature of particular importance in areas of high seismicity.The analysis of shear wall systems is made complex because of the inevitable presence of large openings through these walls. Preliminary analysis can be by truss-analogy, by the finite element method, or by making use of a proprietary computer program designed to consider the interaction, or coupling, of shear walls.Framed or Braced TubesThe concept of the framed or braced or braced tube erupted into the technology with the IBM Building in Pittsburgh, but was followed immediately with the twin 110-story towers of the World Trade Center, New York and a number of other buildings .The system is characterized by three –dimensional frames, braced frames, or shear walls, forming a closed surface more or less cylindrical in nature, but of nearly any plan configuration. Because those columns that resist lateral forces are placed as far as possible from the cancroids of the system, the overall moment of inertia is increased and stiffness is very high.The analysis of tubular structures is done using three-dimensional concepts, or by two- dimensional analogy, where possible, whichever method is used, it must be capable of accounting for the effects of shear lag.The presence of shear lag, detected first in aircraft structures, is a serious limitation in the stiffness of framed tubes. The concept has limited recent applications of framed tubes to the shear of 60 stories. Designers have developed various techniques for reducing the effects of shear lag, most noticeably the use of belt trusses. This system finds application in buildings perhaps 40stories and higher. However, except for possible aesthetic considerations, belt trusses interfere with nearly every building function associated with the outside wall; the trusses are placed often at mechanical floors, mush to the disapproval of the designers of the mechanical systems. Nevertheless, as a cost-effective structural system, the belt truss works well and will likely find continued approval from designers. Numerous studies have sought to optimize the location of these trusses, with the optimum location very dependent on the number of trusses provided. Experience would indicate, however, that the location of these trusses is provided by the optimization of mechanical systems and by aesthetic considerations, as the economics of the structural system is not highly sensitive to belt truss location.Tube-in-Tube StructuresThe tubular framing system mobilizes every column in the exterior wallin resisting over-turning and shearing forces. The term‘tube-in-tube’is largely self-explanatory in that a second ring of columns, the ring surrounding the central service core of the building, is used as an inner framed or braced tube. The purpose of the second tube is to increase resistance to over turning and to increase lateral stiffness. The tubes need not be of the same character; that is, one tube could be framed, while the other could be braced.In considering this system, is important to understand clearly the difference between the shear and the flexural components of deflection, the terms being taken from beam analogy. In a framed tube, the shear component of deflection is associated with the bending deformation of columns and girders , the webs of the framed tube while the flexural component is associated with the axial shortening and lengthening of columns , the flanges of the framed tube. In a braced tube, the shear component of deflection is associated with the axial deformation of diagonals while the flexural component of deflection is associated with the axial shortening and lengthening of columns.Following beam analogy, if plane surfaces remain plane , the floor slabs,then axial stresses in the columns of the outer tube, being farther form the neutral axis, will be substantially larger than the axial stresses in the inner tube. However, in the tube-in-tube design, when optimized, the axial stresses in the inner ring of columns may be as high, or evenhigher, than the axial stresses in the outer ring. This seeming anomaly is associated with differences in the shearing component of stiffness between the two systems. This is easiest to under-stand where the inner tube is conceived as a braced , shear-stiff tube while the outer tube is conceived as a framed , shear-flexible tube.Core Interactive StructuresCore interactive structures are a special case of a tube-in-tube wherein the two tubes are coupled together with some form of three-dimensional space frame. Indeed, the system is used often wherein the shear stiffness of the outer tube is zero. The United States Steel Building, Pittsburgh, illustrates the system very well. Here, the inner tube is a braced frame, the outer tube has no shear stiffness, and the two systems are coupled if they were considered as systems passing in a straight line from the “hat” structure. Note that the exterior columns would be improperly modeled if they were considered as systems passing in a straight line from the “hat” to the foundations; these columns are perhaps 15% stiffer as they follow the elastic curve of the braced core. Note also that the axial forces associated with the lateral forces in the inner columns change from tension to compression over the height of the tube, with the inflection point at about 5/8 of the height of the tube. The outer columns, of course, carry the same axial force under lateral load for the full height of the columns because the columns because the shearstiffness of the system is close to zero.The space structures of outrigger girders or trusses, that connect the inner tube to the outer tube, are located often at several levels in the building. The AT&T headquarters is an example of an astonishing array of interactive elements:1.The structural system is 94 ft wide, 196ft long, and 601ft high.2.Two inner tubes are provided, each 31ft by 40 ft , centered 90 ft apartin the long direction of the building.3.The inner tubes are braced in the short direction, but with zero shearstiffness in the long direction.4.A single outer tube is supplied, which encircles the buildingperimeter.5.The outer tube is a moment-resisting frame, but with zero shearstiffness for the center50ft of each of the long sides.6.A space-truss hat structure is provided at the top of the building.7.A similar space truss is located near the bottom of the building8.The entire assembly is laterally supported at the base on twinsteel-plate tubes, because the shear stiffness of the outer tube goes to zero at the base of the building.Cellular structuresA classic example of a cellular structure is the Sears Tower, Chicago,a bundled tube structure of nine separate tubes. While the Sears Towercontains nine nearly identical tubes, the basic structural system has special application for buildings of irregular shape, as the several tubes need not be similar in plan shape, It is not uncommon that some of the individual tubes one of the strengths and one of the weaknesses of the system.This special weakness of this system, particularly in framed tubes, has to do with the concept of differential column shortening. The shortening of a column under load is given by the expression△=ΣfL/EFor buildings of 12 ft floor-to-floor distances and an average compressive stress of 15 ksi 138MPa, the shortening of a column under load is 15 1212/29,000 or per story. At 50 stories, the column will have shortened to in. 94mm less than its unstressed length. Where one cell of a bundled tube system is, say, 50stories high and an adjacent cell is, say, 100stories high, those columns near the boundary between .the two systems need to have this differential deflection reconciled.Major structural work has been found to be needed at such locations. In at least one building, the Rialto Project, Melbourne, the structural engineer found it necessary to vertically pre-stress the lower height columns so as to reconcile the differential deflections of columns in close proximity with the post-tensioning of the shorter column simulatingthe weight to be added on to adjacent, higher columns.二、原文翻译：抗侧向荷载的结构体系常用的结构体系若已测出荷载量达数千万磅重,那么在高层建筑设计中就没有多少可以进行极其复杂的构思余地了;确实,较好的高层建筑普遍具有构思简单、表现明晰的特点;这并不是说没有进行宏观构思的余地;实际上,正是因为有了这种宏观的构思,新奇的高层建筑体系才得以发展,可能更重要的是：几年以前才出现的一些新概念在今天的技术中已经变得平常了;如果忽略一些与建筑材料密切相关的概念不谈,高层建筑里最为常用的结构体系便可分为如下几类：1．抗弯矩框架;2．支撑框架,包括偏心支撑框架;3．剪力墙,包括钢板剪力墙;4．筒中框架;5．筒中筒结构;6．核心交互结构;7．框格体系或束筒体系;特别是由于最近趋向于更复杂的建筑形式,同时也需要增加刚度以抵抗几力和地震力,大多数高层建筑都具有由框架、支撑构架、剪力墙和相关体系相结合而构成的体系;而且,就较高的建筑物而言,大多数都是由交互式构件组成三维陈列;将这些构件结合起来的方法正是高层建筑设计方法的本质;其结合方式需要在考虑环境、功能和费用后再发展,以便提供促使建筑发展达到新高度的有效结构;这并不是说富于想象力的结构设计就能够创造出伟大建筑;正相反,有许多例优美的建筑仅得到结构工程师适当的支持就被创造出来了,然而,如果没有天赋甚厚的建筑师的创造力的指导,那么,得以发展的就只能是好的结构,并非是伟大的建筑;无论如何,要想创造出高层建筑真正非凡的设计,两者都需要最好的;虽然在文献中通常可以见到有关这七种体系的全面性讨论,但是在这里还值得进一步讨论;设计方法的本质贯穿于整个讨论;设计方法的本质贯穿于整个讨论中;抗弯矩框架抗弯矩框架也许是低,中高度的建筑中常用的体系,它具有线性水平构件和垂直构件在接头处基本刚接之特点;这种框架用作独立的体系,或者和其他体系结合起来使用,以便提供所需要水平荷载抵抗力;对于较高的高层建筑,可能会发现该本系不宜作为独立体系,这是因为在侧向力的作用下难以调动足够的刚度;我们可以利用STRESS,STRUDL 或者其他大量合适的计算机程序进行结构分析;所谓的门架法分析或悬臂法分析在当今的技术中无一席之地,由于柱梁节点固有柔性,并且由于初步设计应该力求突出体系的弱点,所以在初析中使用框架的中心距尺寸设计是司空惯的;当然,在设计的后期阶段,实际地评价结点的变形很有必要;支撑框架支撑框架实际上刚度比抗弯矩框架强,在高层建筑中也得到更广泛的应用;这种体系以其结点处铰接或则接的线性水平构件、垂直构件和斜撑构件而具特色,它通常与其他体系共同用于较高的建筑,并且作为一种独立的体系用在低、中高度的建筑中;尤其引人关注的是,在强震区使用偏心支撑框架;此外,可以利用STRESS,STRUDL,或一系列二维或三维计算机分析程序中的任何一种进行结构分析;另外,初步分析中常用中心距尺寸;剪力墙剪力墙在加强结构体系刚性的发展过程中又前进了一步;该体系的特点是具有相当薄的,通常是而不总是混凝土的构件,这种构件既可提供结构强度,又可提供建筑物功能上的分隔;在高层建筑中,剪力墙体系趋向于具有相对大的高宽经,即与宽度相比,其高度偏大;由于基础体系缺少应力,任何一种结构构件抗倾覆弯矩的能力都受到体系的宽度和构件承受的重力荷载的限制;由于剪力墙宽度狭狭窄受限,所以需要以某种方式加以扩大,以便提从所需的抗倾覆能力;在窗户需要量小的建筑物外墙中明显地使用了这种确有所需要宽度的体系;钢结构剪力墙通常由混凝土覆盖层来加强以抵抗失稳,这在剪切荷载大的地方已得到应用;这种体系实际上比钢支撑经济,对于使剪切荷载由位于地面正上方区域内比较高的楼层向下移特别有效;这种体系还具有高延性之优点,这种特性在强震区特别重要;由于这些墙内必然出同一些大孔,使得剪力墙体系分析变得错综复杂;可以通过桁架模似法、有限元法,或者通过利用为考虑剪力墙的交互作用或扭转功能设计的专门计处机程序进行初步分析框架或支撑式筒体结构：框架或支撑式筒体最先应用于IBM公司在Pittsburgh的一幢办公楼,随后立即被应用于纽约双子座的110层世界贸易中心摩天大楼和其他的建筑中;这种系统有以下几个显着的特征：三维结构、支撑式结构、或由剪力墙形成的一个性质上差不多是圆柱体的闭合曲面,但又有任意的平面构成;由于这些抵抗侧向荷载的柱子差不多都被设置在整个系统的中心,所以整体的惯性得到提高,刚度也是很大的;在可能的情况下,通过三维概念的应用、二维的类比,我们可以进行筒体结构的分析;不管应用那种方法,都必须考虑剪力滞后的影响;这种最先在航天器结构中研究的剪力滞后出现后,对筒体结构的刚度是一个很大的限制;这种观念已经影响了筒体结构在60层以上建筑中的应用;设计者已经开发出了很多的技术,用以减小剪力滞后的影响,这其中最有名的是桁架的应用;框架或支撑式筒体在40层或稍高的建筑中找到了自己的用武之地;除了一些美观的考虑外,桁架几乎很少涉及与外墙联系的每个建筑功能,而悬索一般设置在机械的地板上,这就令机械体系设计师们很不赞成;但是,作为一个性价比较好的结构体系,桁架能充分发挥它的性能,所以它会得到设计师们持续的支持;由于其最佳位置正取决于所提供的桁架的数量,因此很多研究已经试图完善这些构件的位置;实验表明：由于这种结构体系的经济性并不十分受桁架位置的影响,所以这些桁架的位置主要取决于机械系统的完善,审美的要求,筒中筒结构：筒体结构系统能使外墙中的柱具有灵活性,用以抵抗颠覆和剪切力;“筒中筒”这个名字顾名思义就是在建筑物的核心承重部分又被包围了第二层的一系列柱子,它们被当作是框架和支撑筒来使用;配置第二层柱的目的是增强抗颠覆能力和增大侧移刚度;这些筒体不是同样的功能,也就是说,有些筒体是结构的,而有些筒体是用来支撑的;在考虑这种筒体时,清楚的认识和区别变形的剪切和弯曲分量是很重要的,这源于对梁的对比分析;在结构筒中,剪切构件的偏角和柱、纵梁例如：结构筒中的网等的弯曲有关,同时,弯曲构件的偏角取决于柱子的轴心压缩和延伸例如：结构筒的边缘等;在支撑筒中,剪切构件的偏角和对角线的轴心变形有关,而弯曲构件的偏角则与柱子的轴心压缩和延伸有关;根据梁的对比分析,如果平面保持原形例如：厚楼板,那么外层筒中柱的轴心压力就会与中心筒柱的轴心压力相差甚远,而且稳定的大于中心筒;但是在筒中筒结构的设计中,当发展到极限时,内部轴心压力会很高的,甚至远远大于外部的柱子;这种反常的现象是由于两种体系中的剪切构件的刚度不同;这很容易去理解,内筒可以看成是一个支撑或者说是剪切刚性的筒,而外筒可以看成是一个结构或者说是剪切弹性的筒;核心交互式结构：核心交互式结构属于两个筒与某些形式的三维空间框架相配合的筒中筒特殊情况;事实上,这种体系常用于那种外筒剪切刚度为零的结构;位于Pittsburgh的美国钢铁大楼证实了这种体系是能很好的工作的;在核心交互式结构中,内筒是一个支撑结构,外筒没有任何剪切刚度,而且两种结构体系能通过一个空间结构或“帽”式结构共同起作用;需要指出的是,如果把外部的柱子看成是一种从“帽”到基础的直线体系,这将是不合适的；根据支撑核心的弹性曲线,这些柱子只发挥了刚度的15%;同样需要指出的是,内柱中与侧向力有关的轴向力沿筒高度由拉力变为压力,同时变化点位于筒高度的约5/8处;当然,外柱也传递相同的轴向力,这种轴向力低于作用在整个柱子高度的侧向荷载,因为这个体系的剪切刚度接近于零;把内外筒相连接的空间结构、悬臂梁或桁架经常遵照一些规范来布置;美国电话电报总局就是一个布置交互式构件的生动例子;1、结构体系长米,宽米,高米;2、布置了两个筒,每个筒的尺寸是米×米,在长方向上有米的间隔;3、在短方向上内筒被支撑起来,但是在长方向上没有剪切刚度;4、环绕着建筑物布置了一个外筒;5、外筒是一个瞬时抵抗结构,但是在每个长方向的中心米都没有剪切刚度;6、在建筑的顶部布置了一个空间桁架构成的“帽式”结构;7、在建筑的底部布置了一个相似的空间桁架结构;8、由于外筒的剪切刚度在建筑的底部接近零,整个建筑基本上由两个钢板筒来支持;框格体系或束筒体系结构：位于美国芝加哥的西尔斯大厦是箱式结构的经典之作,它由九个相互独立的筒组成的一个集中筒;由于西尔斯大厦包括九个几乎垂直的筒,而且筒在平面上无须相似,基本的结构体系在不规则形状的建筑中得到特别的应用;一些单个的筒高于建筑一点或很多是很常见的;事实上,这种体系的重要特征就在于它既有坚固的一面,也有脆弱的一面;这种体系的脆弱,特别是在结构筒中,与柱子的压缩变形有很大的关系,柱子的压缩变形有下式计算：△=ΣfL/E对于那些层高为米左右和平均压力为138MPa的建筑,在荷载作用下每层柱子的压缩变形为1512/29000或毫米;在第50层柱子会压缩94毫米,小于它未受压的长度;这些柱子在50层的时候和100层的时候的变形是不一样的,位于这两种体系之间接近于边缘的那些柱需要使这种不均匀的变形得以调解;主要的结构工作都集中在布置中;在Melbourne的Rialto项目中,结构工程师发现至少有一幢建筑,很有必要垂直预压低高度的柱子,以便使柱不均匀的变形差得以调解,调解的方法近似于后拉伸法,即较短的柱转移重量到较高的邻柱上;。
(完整版)土木工程专业英语课文原文及对照翻译
Civil EngineeringCivil engineering, the oldest of the engineering specialties, is the planning, design, construction, and management of the built environment. This environment includes all structures built according to scientific principles, from irrigation and drainage systems to rocket-launching facilities.土木工程学作为最老的工程技术学科，是指规划，设计，施工及对建筑环境的管理。
此处的环境包括建筑符合科学规范的所有结构，从灌溉和排水系统到火箭发射设施。
Civil engineers build roads, bridges, tunnels, dams, harbors, power plants, water and sewage systems, hospitals, schools, mass transit, and other public facilities essential to modern society and large population concentrations. They also build privately owned facilities such as airports, railroads, pipelines, skyscrapers, and other large structures designed for industrial, commercial, or residential use. In addition, civil engineers plan, design, and build complete cities and towns, and more recently have been planning and designing space platforms to house self-contained communities.土木工程师建造道路，桥梁，管道，大坝，海港，发电厂，给排水系统，医院，学校，公共交通和其他现代社会和大量人口集中地区的基础公共设施。
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Design, Construction & Structural Details of Burj DubaiThe goal of the Burj Dubai Tower is not simply to be the world's highest building: it's to embody the world's highest aspirations. The superstructure is currently under construction and as of fall 2007 has reached over 160 stories. The final height of the building is 2,717 feet (828 meters). The height of the multi-use skyscraper will "comfortably" exceed the current record holder, the 509 meter (1671 ft) tall Taipei 101. The 280,000 m2(3,000,000 ft2) reinforced concrete multi-use Burj Dubai tower is utilized for retail, a Giorgio Armani Hotel, residential and office. As with all super-tall projects, difficult structural engineering problems needed to be addressed and resolved。
Structural System DescriptionBurj Khalifa has "refuge floors" at 25 to 30 story intervals that are more fire resistant and have separate air supplies in case of emergency. Its reinforced concrete structure makes it stronger than steel-frame skyscrapersDesigners purposely shaped the structural concrete Burj Dubai - "Y" shaped in plan - to reduce the wind forces on the tower, as well as to keep the structure simple and foster constructibility. The structural system can be described as a "buttressed" core (Figures 1, 2 and 3). Each wing, with its own high performance concrete corridor walls and perimeter columns, buttresses the others via a six-sided central core, or hexagonal hub. The result is a tower that is extremely stiff laterally and torsionally. SOM applied a rigorous geometry to the tower that aligned all the common central core, wall, and column elements。
Each tier of the building sets back in a spiral stepping pattern up the building. The setbacks are organized with the Tower's grid, such that the building stepping is accomplished by aligning columns above with walls below to provide a smooth load path. This allows the construction to proceed without the normal difficulties associated with column transfers The setbacks are organized such that the Tower's width changes at each setback. The advantage of the stepping and shaping is to "confuse the wind'1. The wind vortices never get organized because at each new tier the wind encounters a different building shape.The Tower and Podium structures are currently under construction (Figure 3) and the project is scheduled for topping out in 2008。
Architectural DesignThe context of the Burj Dubai being located in the city of Dubai, UAE, drove the inspiration for the building form to incorporate cultural, historical, and organic influences particular to the region。
The center hexagonal reinforced concrete core walls provide the torsional resistance of the structure similar to a closed tube or axle. The center hexagonal walls are buttressed by the wing walls and hammer head walls which behave as the webs and flanges of a beam to resist the wind shears and moments.Outriggers at the mechanical floors allow the columns to participate in the lateral load resistance of the structure; hence, all of the vertical concrete is utilized to support both gravity and lateral loads. The wall concrete specified strengths ranged from C80 to C60 cube strength and utilized Portland cement and fly ashLocal aggregates were utilized for the concrete mix design. The C80 concrete for the lower portion of the structure had a specified Young's Elastic Modulus of 43,800 N/mm2 (6,350ksi) at 90 days. The wall and column sizes were optimized using virtual work .' La Grange multiplier methodology which results in a very efficient structure (Baker et ah, 2000). The reinforced concrete structure was designed in accordance with the requirements of ACI 318-02 Building Code Requirements for Structural ConcreteThe wall thicknesses and column sizes were fine-tuned to reduce the effects of creep and shrinkage on the individual elements which compose the structure. To reduce the effects of differential column shortening, due to creep, between the perimeter columns and interior walls, the perimeter columns were sized such that the self-weight gravity stress on the perimeter columns matched the stress on the interior corridor walls. The five (5) sets of outriggers, distributed up the building, tie all the vertical load carrying elements together, further ensuring uniform gravity stresses: hence, reducing differential creep movements. Since the shrinkage in concrete occurs more quickly in thinner walls or columns, the perimeter column thickness of 600mm (24") matched the typical corridor wall thickness (similar volume to surface ratios) (Figure 5) to ensure the columns and walls will generally shorten at the same rate due to concrete shrinkageThe top section of the Tower consists of a structural steel spire utilizing a diagonally braced lateral system. The structural steel spire was designed for gravity, wind, seismic and fatigue in accordance with therequirements of AISC Load and Resistance Factor Design Specification for Structural Steel Buildings (1999). The exterior exposed steel is protected with a flame applied aluminum finish.Analysis for GravityThe structure was analyzed for gravity (including P-Delta analysis), wind, and seismic loadings by ETABS version 8.4 (Figure 6). The three-dimensional analysis model consisted of the reinforced concrete walls, link beams, slabs, raft, piles, and the spire structural steel system. The full 3D analysis model consisted of over 73,500 shells and 75,000 nodes. Under lateral wind loading, the building deflections are well below commonly used criteria. The dynamic analysis indicated the first mode is lateral side sway with a period of 11.3 seconds (Figure 7). The second mode is a perpendicular lateral side sway with a period of 10.2 seconds. Torsion is the fifth mode with a period of 4.3 secondsSite Test and AnalysisThe Dubai Municipality (DM) specifies Dubai as a UBC97 Zone 2a seismic region (with a seismic zone facior Z = 0.15 and soil profile Sc). The seismic analysis consisted of a site specific response spectra analysis. Seismic loading typically did not govern the design of the reinforced concrete Tower structure. Seismic loading did govern the design of the reinforced concrete Podium buildings and the Tower structural steel spire Dr. Max Irvine (with Structural Mechanics & Dynamics Consulting Engineers located in Sydney Australia) developed site specific seismic reports for the project including a seismic hazard analysis. The potential for liquefaction was investigated based on several accepted methods; it was determined that liquefaction is not considered to have any structural implications for the deep seated Tower foundations.In addition to the standard cube tests, the raft concrete was field tested prior to placement by flow table (Figure 10). L-box, V-Box and temperature The Tower foundations consist of a pile supported raft. The solid reinforced concrete raft is 3.7 meters (12 ft) thick and was poured utilizing C50 (cube strength) self consolidating concrete (SCC). The raft was constructed in four (4) separate pours (three wings and the center core). Each raft pour occurred over at least a 24 hour period. Reinforcement was typically at 300mm spacing in the raft, and arranged such that every 10lh bar in each direction was omitted, resulting in a series of "pour enhancement strips" throughout the raft at which 600 mm x 600 mm openings at regular intervals facilitated access and concrete placement.The Tower raft is supported by 194 bored cast-in-place piles. The piles are 1.5 meter in diameter and approximately 43 meters long with a design capacity of 3,000 tonnes each. The Tower pile load test supported over 6,000 tonnes (Figure 12). The C60 (cube strength) SCC concrete was placed by the tremie method utilizing polymer slurry. The friction piles are supported in the naturally cemented calcisiltite conglomeritic 聚结calcisiltite fomiations developing an ultimate pile skin friction of 250 to 350 kPa (2.6 to 3.6 tons / ft ). When the rebar cage was placed in the piles, special attention was paid to orient the rebar cage such that the raft bottom rebar could be threaded through the numerous pile rebar cages without interruption, which greatly simplified the raft construction.1.The site geotechnical investigation consisted of the followingPhases。