土木工程外文翻译
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。
土木工程 外文资料翻译(通用)
淮阴工学院毕业设计外文资料翻译学院：建筑工程学院专业：土木工程（路桥方向）姓名：石洋学号：1081401526外文出处：工程力学杂志(用外文写)Journal of Engineering Mechanics 附件： 1.外文资料翻译译文；2.外文原文。
注：请将该封面与附件装订成册。
附件1：外文资料翻译译文Timoshenko 和剪切模型梁的动力学研究Noël Challamel1摘要：古典Timoshenko 梁模型和剪切梁模型常用于建筑行为模型都剪稳定性或动态分析。
该技术关注的是两种模型间的大量弯曲剪切刚度值的问题。
这是以两种模型分析研究了简支梁。
获得大量弯曲剪切刚度值的渐进解。
在一般情况下，实验在考虑大弯剪刚度值参数时证明该剪切梁模型不能从Timoshenko 模型中推断出来，这只是达到特定的几何参数在目前的例子。
作为结论，剪切模型的能力近似Timoshenko 模型，因为大量弯曲剪切刚度参数是坚定的依赖于横截面在边界状态下的材料和几何特性。
关键词：横波，结构力学，动态模型，脑电图仪，比较研究。
引言：经典的Timoshenko 梁模型和剪切梁模型经常被用来模拟建筑物的剪切稳定性和动态特性。
该技术关注的是两种模型间的大量弯曲剪切刚度值的问题。
2004年Aristizabal-Ochoa 通过考虑大量无维参数来比较这两种模型出一种关系，屈服于剪切刚度参数。
这项科学证据表明一个简单的例子这个参数可能不足以联系这两种理论。
Timoshenko 模型动态方程： Timoshenko 模型的控制方程是：x∂θ∂EI -)θ-x ∂y ∂(G A -t ∂θ∂r m 0x∂θ∂G A x ∂y ∂G A -t ∂∂m 22S 222S 22S 2y 2==+ (1) 这种横梁只在杨氏模量和横断面剪切模量下用均匀的弹性材料制成的。
它的横向的横截面是带有一个用A S 和一个重要的惯性矩表示的有效的剪切区域双重对称的I =Ar 2。
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
土木工程外文翻译-原文
外文原文Response of a reinforced concrete infilled-frame structure to removal of twoadjacent columnsMehrdad Sasani_Northeastern University, 400 Snell Engineering Center, Boston, MA 02115, UnitedStatesReceived 27 June 2007; received in revised form 26 December 2007; accepted 24January 2008Available online 19 March 2008AbstractThe response of Hotel San Diego, a six-story reinforced concrete infilled-frame structure, is evaluated following the simultaneous removal of two adjacent exterior columns. Analytical models of the structure using the Finite Element Method as well as the Applied Element Method are used to calculate global and local deformations. The analytical results show good agreement with experimental data. The structure resisted progressive collapse with a measured maximum vertical displacement of only one quarter of an inch (6.4 mm). Deformation propagation over the height of the structure and the dynamic load redistribution following the column removal are experimentally and analytically evaluated and described. The difference between axial and flexural wave propagations is discussed. Three-dimensional Vierendeel (frame) action of the transverse and longitudinal frames with the participation of infill walls is identified as the major mechanism for redistribution of loads in the structure. The effects of two potential brittle modes of failure (fracture of beam sections without tensile reinforcement and reinforcing bar pull out) are described. The response of the structure due to additional gravity loads and in the absence of infill walls is analytically evaluated.c 2008 Elsevier Ltd. All rights reserved.Keywords: Progressive collapse; Load redistribution; Load resistance; Dynamic response; Nonlinear analysis; Brittle failure1.IntroductionThe principal scope of specifications is to provide general principles and computation al methods in order to verify safety of structures. The “ safety factor ”, which accor ding to modern trends is independent of the nature and combination of the materials u sed, can usually be defined as the ratio between the conditions. This ratio is also prop ortional 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 un serviceability 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 desi gned for. There are two categories of limit state :(1)Ultimate limit sate, which corresponds to the highest value of the load-bearing cap acity. 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 t he 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. E xamples include excessive deformations and displacements without instability; early o r excessive cracks; large vibrations; and corrosion.Computational methods used to verify structures with respect to the different safety co nditions 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 para meters.Alternatively, with respect to the different use of factors of safety, computational meth ods 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 u seful computational methods. Generally, two combinations prevail:(1)deterministic methods, which make use of allowable stresses. (2)Probabilistic meth ods, 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 combin ed to define the safety factor. probabilistic approaches depend upon :(1) Random distribution of strength of materials with respect to the conditions of fabri cation and erection ( scatter of the values of mechanical properties through out the str ucture ); (2) Uncertainty of the geometry of the cross-section sand of the structure ( fa ults 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)U ncertainty related to the approximation of the computational method used ( deviation of the actual stresses from computed stresses ). Furthermore, probabilistic theories me an 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)Numbe r of human lives which can be threatened by this failure; (3)Possibility and/or likeliho od of repairing the structure; (4) Predicted life of the structure. All these factors are rel ated 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 constructio n 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 mat erials, and of the geometry of the cross-sections and the structure have to be known. F urthermore, 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 t he 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 mate rial and to the loads, without necessarily adopting the probabilistic criterion. The seco nd is an approximate probabilistic method which introduces some simplifying assump tions ( semi-probabilistic methods ) . As part of mitigation programs to reduce the likelihood of mass casualties following local damage in structures, the General Services Administration [1] and the Department of Defense [2] developed regulations to evaluate progressive collapse resistance of structures. ASCE/SEI 7 [3] defines progressive collapse as the spread of an initial local failure from element to element eventually resulting in collapse of an entire structure or a disproportionately large part of it. Following the approaches proposed by Ellinwood and Leyendecker [4], ASCE/SEI 7 [3] defines two general methods for structural design of buildings to mitigate damage due to progressive collapse: indirect and direct design methods. General building codes and standards [3,5] use indirect design by increasing overall integrity of structures. Indirect design is also used in DOD [2]. Although the indirect design method can reduce the risk of progressive collapse [6,7] estimation of post-failure performance of structures designed based on such a method is not readily possible. One approach based on direct design methods to evaluate progressive collapse of structures is to study the effects of instantaneous removal of load-bearing elements, such as columns. GSA [1] and DOD [2] regulations require removal of one load bearing element. These regulations are meant to evaluate general integrity of structures and their capacity of redistributing the loads following severe damage to only one element. While such an approach provides insight as to the extent to which the structures are susceptible to progressive collapse, in reality, the initial damage can affect more than just one column. In this study, using analytical results that are verified against experimental data, the progressive collapse resistance of the Hotel San Diego is evaluated, following the simultaneous explosion (sudden removal) of two adjacent columns, one of which was a corner column. In order to explode the columns, explosives were inserted into predrilled holes in the columns. The columns were then well wrapped with a few layers of protective materials. Therefore, neither air blast nor flying fragments affected the structure.2. Building characteristicsHotel San Diego was constructed in 1914 with a south annex added in 1924. The annex included two separate buildings. Fig. 1 shows a south view of the hotel. Note that in the picture, the first and third stories of the hotel are covered with black fabric. The six story hotel had a non-ductile reinforced concrete (RC) frame structure with hollow clay tile exterior infill walls. The infills in the annex consisted of two withes (layers) of clay tiles with a total thickness of about 8 in (203 mm). The height of the first floor was about 190–800 (6.00 m). The height of other floors and that of the top floor were 100–600 (3.20 m) and 160–1000 (5.13 m), respectively. Fig. 2 shows the second floor of one of the annex buildings. Fig. 3 shows a typical plan of this building, whose response following the simultaneous removal (explosion) of columns A2 and A3 in the first (ground) floor is evaluated in this paper. The floor system consisted of one-way joists running in the longitudinal direction (North–South), as shown in Fig. 3. Based on compression tests of two concrete samples, the average concrete compressive strength was estimated at about 4500 psi (31 MPa) for a standard concrete cylinder. The modulus of elasticity of concrete was estimated at 3820 ksi (26 300 MPa) [5]. Also, based on tension tests of two steel samples having 1/2 in (12.7 mm) square sections, the yield and ultimate tensile strengths were found to be 62 ksi (427 MPa) and 87 ksi (600 MPa), respectively. The steel ultimate tensile strain was measured at 0.17. The modulus of elasticity of steel was set equal to 29 000 ksi (200000 MPa). The building was scheduled to be demolished by implosion. As part of the demolition process, the infill walls were removed from the first and third floors. There was no live load in the building. All nonstructural elements including partitions, plumbing, and furniture were removed prior to implosion. Only beams, columns, joist floor and infill walls on the peripheralbeams were present.3. SensorsConcrete and steel strain gages were used to measure changes in strains of beams and columns. Linear potentiometers were used to measure global and local deformations. The concrete strain gages were 3.5 in (90 mm) long having a maximum strain limit of ±0.02. The steel strain gages could measure up to a strain of ±0.20. The strain gages could operate up to a several hundred kHz sampling rate. The sampling rate used in the experiment was 1000 Hz. Potentiometers were used to capture rotation (integral of curvature over a length) of the beam end regions and global displacement in the building, as described later. The potentiometers had a resolution of about 0.0004 in (0.01 mm) and a maximum operational speed of about 40 in/s (1.0 m/s), while the maximum recorded speed in the experiment was about 14 in/s (0.35m/s).4. Finite element modelUsing the finite element method (FEM), a model of the building was developed in the SAP2000 [8] computer program. The beams and columns are modeled with Bernoulli beam elements. Beams have T or L sections with effective flange width on each side of the web equal to four times the slab thickness [5]. Plastic hinges are assigned to all possible locations where steel bar yielding can occur, including the ends of elements as well as the reinforcing bar cut-off and bend locations. The characteristics of the plastic hinges are obtained using section analyses of the beams and columns and assuming a plastic hinge length equal to half of the section depth. The current version of SAP2000 [8] is not able to track formation of cracks in the elements. In order to find the proper flexural stiffness of sections, an iterative procedure is used as follows. First, the building is analyzed assuming all elements are uncracked. Then, moment demands in the elements are compared with their cracking bending moments, Mcr . The moment of inertia of beam and slab segments are reduced by a coefficient of 0.35 [5], where the demand exceeds the Mcr. The exteriorbeam cracking bending moments under negative and positive moments, are 516 k in (58.2 kN m) and 336 k in (37.9 kN m), respectively. Note that no cracks were formed in the columns. Then the building is reanalyzed and moment diagrams are re-evaluated. This procedure is repeated until all of the cracked regions are properly identified and modeled.The beams in the building did not have top reinforcing bars except at the end regions (see Fig. 4). For instance, no top reinforcement was provided beyond the bend in beam A1–A2, 12 inches away from the face of column A1 (see Figs. 4 and 5). To model the potential loss of flexural strength in those sections, localized crack hinges were assigned at the critical locations where no top rebar was present. Flexural strengths of the hinges were set equal to Mcr. Such sections were assumed to lose their flexural strength when the imposed bending moments reached Mcr.The floor system consisted of joists in the longitudinal direction (North–South). Fig. 6 shows the cross section of a typical floor. In order to account for potential nonlinear response of slabs and joists, floors are molded by beam elements. Joists are modeled with T-sections, having effective flange width on each side of the web equal to four times the slab thickness [5]. Given the large joist spacing between axes 2 and 3, two rectangular beam elements with 20-inch wide sections are used between the joist and the longitudinal beams of axes 2 and 3 to model the slab in the longitudinal direction. To model the behavior of the slab in the transverse direction, equally spaced parallel beams with 20-inch wide rectangular sections are used. There is a difference between the shear flow in the slab and that in the beam elements with rectangular sections modeling the slab. Because of this, the torsional stiffness is setequal to one-half of that of the gross sections [9].The building had infill walls on 2nd, 4th, 5th and 6th floors on the spandrel beamswith some openings (i.e. windows and doors). As mentioned before and as part of the demolition procedure, the infill walls in the 1st and 3rd floors were removed before the test. The infill walls were made of hollow clay tiles, which were in good condition. The net area of the clay tiles was about 1/2 of the gross area. The in-plane action of the infill walls contributes to the building stiffness and strength and affects the building response. Ignoring the effects of the infill walls and excluding them in the model would result in underestimating the building stiffness and strength.Using the SAP2000 computer program [8], two types of modeling for the infills are considered in this study: one uses two dimensional shell elements (Model A) and the other uses compressive struts (Model B) as suggested in FEMA356 [10] guidelines.4.1. Model A (infills modeled by shell elements)Infill walls are modeled with shell elements. However, the current version of the SAP2000 computer program includes only linear shell elements and cannot account for cracking. The tensile strength of the infill walls is set equal to 26 psi, with a modulus of elasticity of 644 ksi [10]. Because the formation ofcracks has a significant effect on the stiffness of the infill walls, the following iterative procedure is used to account for crack formation:(1) Assuming the infill walls are linear and uncracked, a nonlinear time history analysis is run. Note that plastic hinges exist in the beam elements and the segments of the beam elements where moment demand exceeds the cracking moment have a reduced moment of inertia.(2) The cracking pattern in the infill wall is determined by comparing stresses in the shells developed during the analysis with the tensile strength of infills.(3) Nodes are separated at the locations where tensile stress exceeds tensile strength. These steps are continued until the crack regions are properly modeled.4.2. Model B (infills modeled by struts)Infill walls are replaced with compressive struts as described in FEMA 356 [10] guidelines. Orientations of the struts are determined from the deformed shape of the structure after column removal and the location of openings.4.3. Column removalRemoval of the columns is simulated with the following procedure.(1) The structure is analyzed under the permanent loads and the internal forces are determined at the ends of the columns, which will be removed.(2) The model is modified by removing columns A2 and A3 on the first floor. Again the structure is statically analyzed under permanent loads. In this case, the internal forces at the ends of removed columns found in the first step are applied externally to the structure along with permanent loads. Note that the results of this analysis are identical to those of step 1.(3) The equal and opposite column end forces that were applied in the second step are dynamically imposed on the ends of the removed column within one millisecond [11] to simulate the removal of the columns, and dynamic analysis is conducted.4.4. Comparison of analytical and experimental resultsThe maximum calculated vertical displacement of the building occurs at joint A3 inthe second floor. Fig. 7 shows the experimental and analytical (Model A) vertical displacements of this joint (the AEM results will be discussed in the next section). Experimental data is obtained using the recordings of three potentiometers attached to joint A3 on one of their ends, and to the ground on the other ends. The peak displacements obtained experimentally and analytically (Model A) are 0.242 in (6.1 mm) and 0.252 in (6.4 mm), respectively, which differ only by about 4%. The experimental and analytical times corresponding to peak displacement are 0.069 s and 0.066 s, respectively. The analytical results show a permanent displacement of about 0.208 in (5.3 mm), which is about 14% smaller than the corresponding experimental value of 0.242 in (6.1 mm).Fig. 8 compares vertical displacement histories of joint A3 in the second floor estimated analytically based on Models A and B. As can be seen, modeling infills with struts (Model B) results in a maximum vertical displacement of joint A3 equal to about 0.45 in (11.4 mm), which is approximately 80% larger than the value obtained from Model A. Note that the results obtained from Model A are in close agreement with experimental results (see Fig. 7), while Model B significantly overestimates the deformation of the structure. If the maximum vertical displacement were larger, the infill walls were more severely cracked and the struts were more completely formed, the difference between the results of the two models (Models A and B) would be smaller.Fig. 9 compares the experimental and analytical (Model A) displacement of joint A2 in the second floor. Again, while the first peak vertical displacement obtained experimentally and analytically are in good agreement, the analytical permanent displacement under estimates the experimental value.Analytically estimated deformed shapes of the structure at the maximum vertical displacement based on Model A are shown in Fig. 10 with a magnification factor of 200. The experimentally measured deformed shape over the end regions of beamsA1–A2 and A3–B3 in the second floorare represented in the figure by solid lines. A total of 14 potentiometers were located at the top and bottom of the end regions of the second floor beams A1–A2 and A3–B3, which were the most critical elements in load redistribution. The beam top and corresponding bottom potentiometer recordings were used to calculate rotation between the sections where the potentiometer ends were connected. This was done by first finding the difference between the recorded deformations at the top and bottom of the beam, and then dividing the value by the distance (along the height of the beam section) between the two potentiometers. The expected deformed shapes between the measured end regions of the second floor beams are shown by dashed lines. As can be seen in the figures, analytically estimated deformed shapes of the beams are in good agreement with experimentally obtained deformed shapes.Analytical results of Model A show that only two plastic hinges are formed indicating rebar yielding. Also, four sections that did not have negative (top) reinforcement, reached cracking moment capacities and therefore cracked. Fig. 10 shows the locations of all the formed plastic hinges and cracks.。
土木工程专业英语词汇(整理版)
第一局部必须掌握，第二局部尽量掌握第一局部：1 Finite Element Method 有限单元法2 专业英语Specialty English3 水利工程Hydraulic Engineering4 土木工程Civil Engineering5 地下工程Underground Engineering6 岩土工程Geotechnical Engineering7 道路工程Road (Highway) Engineering8 桥梁工程Bridge Engineering9 隧道工程Tunnel Engineering10 工程力学Engineering Mechanics11 交通工程Traffic Engineering12 港口工程Port Engineering13 平安性safety17木结构timber structure18 砌体结构masonry structure19 混凝土结构concrete structure20 钢结构steelstructure21 钢-混凝土复合结构steel and concrete composite structure22 素混凝土plain concrete23 钢筋混凝土reinforced concrete24 钢筋rebar25 预应力混凝土pre-stressed concrete26 静定结构statically determinate structure27 超静定结构statically indeterminate structure28 桁架结构truss structure29 空间网架结构spatial grid structure30 近海工程offshore engineering31 静力学statics32运动学kinematics33 动力学dynamics34 简支梁simply supported beam35 固定支座fixed bearing36弹性力学elasticity37 塑性力学plasticity38 弹塑性力学elaso-plasticity39 断裂力学fracture Mechanics40 土力学soil mechanics41 水力学hydraulics42 流体力学fluid mechanics43 固体力学solid mechanics44 集中力concentrated force45 压力pressure46 静水压力hydrostatic pressure47 均布压力uniform pressure48 体力body force49 重力gravity 50 线荷载line load51 弯矩bending moment52 torque 扭矩53 应力stress54 应变stain55 正应力normal stress56 剪应力shearing stress57 主应力principal stress58 变形deformation59 内力internal force60 偏移量挠度deflection61 settlement 沉降62 屈曲失稳buckle63 轴力axial force64 允许应力allowable stress65 疲劳分析fatigue analysis66 梁beam67 壳shell68 板plate69 桥bridge70 桩pile71 主动土压力active earth pressure72 被动土压力passive earth pressure73 承载力load-bearing capacity74 水位water Height75 位移displacement76 结构力学structural mechanics77 材料力学material mechanics78 经纬仪altometer79 水准仪level80 学科discipline81 子学科sub-discipline82 期刊journal ,periodical83文献literature84 ISSN International Standard Serial Number 国际标准刊号85 ISBN International Standard Book Number 国际标准书号86 卷volume87 期number 88 专著monograph89 会议论文集Proceeding90 学位论文thesis, dissertation91 专利patent92 档案档案室archive93 国际学术会议conference94 导师advisor95 学位论文辩论defense of thesis96 博士研究生doctorate student97 研究生postgraduate98 EI Engineering Index 工程索引99 SCI Science Citation Index 科学引文索引100ISTP Index to Science and Technology Proceedings 科学技术会议论文集索引101 题目title102 摘要abstract103 全文full-text104 参考文献reference105 联络单位、所属单位affiliation106 主题词Subject107 关键字keyword108 ASCE American Society of Civil Engineers 美国土木工程师协会109 FHWA Federal Highway Administration 联邦公路总署110 ISO International Standard Organization111 解析方法analytical method112 数值方法numerical method113 计算computation114 说明书instruction第二局部：岩土工程专业词汇1.geotechnical engineering岩土工程2.foundation engineering根底工程3.soil, earth土4.soil mechanics土力学cyclic loading周期荷载unloading卸载reloading再加载viscoelastic foundation粘弹性地基viscous damping粘滞阻尼shear modulus剪切模量5.soil dynamics土动力学6.stress path应力路径7.numerical geotechanics 数值岩土力学二. 土的分类 1.residual soil残积土 groundwater level地下水位 2.groundwater 地下水 groundwater table地下水位 3.clay minerals粘土矿物 4.secondary minerals次生矿物 ndslides滑坡 6.bore hole columnar section钻孔柱状图 7.engineering geologic investigation工程地质勘察 8.boulder漂石 9.cobble卵石 10.gravel砂石 11.gravelly sand砾砂 12.coarse sand粗砂 13.medium sand中砂 14.fine sand细砂 15.silty sand粉土 16.clayey soil粘性土 17.clay粘土 18.silty clay粉质粘土 19.silt粉土 20.sandy silt砂质粉土 21.clayey silt粘质粉土 22.saturated soil饱和土 23.unsaturated soil非饱和土 24.fill (soil)填土 25.overconsolidated soil超固结土 26.normally consolidated soil正常固结土 27.underconsolidated soil欠固结土 28.zonal soil区域性土 29.soft clay软粘土 30.expansive (swelling) soil膨胀土 31.peat泥炭 32.loess黄土 33.frozen soil冻土 24.degree of saturation饱和度 25.dry unit weight干重度26.moist unit weight湿重度45.ISSMGE=International Society for Soil Mechanics and Ge otechnical Engineering 国际土力学与岩土工程学会四. 渗透性和渗流1.Darcy’s law 达西定律2.piping管涌3.flowing soil流土4.sand boiling砂沸5.flow net流网6.seepage渗透〔流〕7.leakage渗流8.seepage pressure渗透压力9.permeability渗透性10.seepage force渗透力11.hydraulic gradient水力梯度 12.coefficient of permeability 渗透系数五. 地基应力和变形1.soft soil软土2.(negative) skin friction of driven pile打入桩〔负〕摩阻力3.effective stress有效应力4.total stress总应力5.field vane shear strength十字板抗剪强度6.low activity低活性7.sensitivity灵敏度8.triaxial test三轴试验9.foundation design根底设计 10.recompaction再压缩11.bearing capacity承载力 12.soil mass土体13.contact stress (pressure)接触应力〔压力〕14.concentrated load集中荷载 15.a semi-infinite elastic solid 半无限弹性体 16.homogeneous均质 17.isotropic各向同性 18.strip footing条基 19.square spread footing方形独立根底20.underlying soil (stratum ,strata)下卧层〔土〕21.dead load =sustained load恒载持续荷载 22.live load活载 23.short –term transient load短期瞬时荷载24.long-term transient load长期荷载 25.reduced load折算荷载 26.settlement沉降 27.deformation变形 28.casing套管 29.dike=dyke堤〔防〕 30.clay fraction粘粒粒组 31.physical properties物理性质 32.subgrade路基 33.well-graded soil级配良好土 34.poorly-graded soil级配不良土 35.normal stresses正应力 36.shear stresses剪应力 37.principal plane主平面38.major (intermediate, minor) principal stress最大〔中、最小〕主应力 39.Mohr-Coulomb failure condition摩尔-库仑破坏条件 40.FEM=finite element method有限元法41.limit equilibrium method极限平衡法42.pore water pressure孔隙水压力43.preconsolidation pressure先期固结压力44.modulus of compressibility压缩模量45.coefficent of compressibility压缩系数46 pression index压缩指数 47.swelling index回弹指数 48.geostatic stress自重应力 49.additional stress附加应力 50.total stress总应力 51.final settlement最终沉降 52.slip line滑动线六. 基坑开挖与降水 1 excavation开挖〔挖方〕 2 dewatering 〔基坑〕降水 3 failure of foundation基坑失稳4 bracing of foundation pit基坑围护5 bottom heave=basal heave 〔基坑〕底隆起6 retaining wall挡土墙7 pore-pressure distribution孔压分布 8 dewatering method降低地下水位法 9 well point system 井点系统〔轻型〕 10 deep well point深井点 11 vacuum well point真空井点 12 braced cuts支撑围护 13 braced excavation支撑开挖 14 braced sheeting支撑挡板七. 深根底--deep foundation 1.pile foundation桩根底1)cast –in-place灌注桩 diving casting cast-in-place pile沉管灌注桩 bored pile钻孔桩 special-shaped cast-in-place pile机控异型灌注桩 piles set into rock嵌岩灌注桩 rammed bulb pile夯扩桩2)belled pier foundation钻孔墩根底 drilled-pier foundation 钻孔扩底墩 under-reamed bored pier3)precast concrete pile预制混凝土桩4)steel pile钢桩 steel pipe pile钢管桩 steel sheet pile钢板桩5)prestressed concrete pile预应力混凝土桩 prestressed concrete pipe pile预应力混凝土管桩 2.caisson foundation沉井〔箱〕 3.diaphragm wall地下连续墙截水墙 4.friction pile摩擦桩 5.end-bearing pile端承桩 6.shaft竖井；桩身 7.wave equation analysis波动方程分析 8.pile caps承台〔桩帽〕 9.bearing capacity of single pile 单桩承载力 teral pile load test单桩横向载荷试验 11.ultimate lateral resistance of single pile单桩横向极限承载力 12.static load test of pile单桩竖向静荷载试验 13.vertical allowable load capacity单桩竖向容许承载力 14.low pile cap低桩承台 15.high-rise pile cap高桩承台 16.vertical ultimate uplift resistance of single pile单桩抗拔极限承载力 17.silent piling静力压桩 18.uplift pile抗拔桩 19.anti-slide pile抗滑桩20.pile groups群桩 21.efficiency factor of pile groups群桩效率系数〔η〕22.efficiency of pile groups群桩效应 23.dynamic pile testing 桩基动测技术24.final set最后贯入度 25.dynamic load test of pile桩动荷载试验26.pile integrity test桩的完整性试验 27.pile head=butt桩头 28.pile tip=pile point=pile toe桩端〔头〕 29.pile spacing 桩距30.pile plan桩位布置图 31.arrangement of piles =pile layout 桩的布置32.group action群桩作用 33.end bearing=tip resistance桩端阻 34.skin(side) friction=shaft resistance桩侧阻35.pile cushion桩垫 36.pile driving(by vibration) 〔振动〕打桩 37.pile pulling test拔桩试验 38.pile shoe桩靴 39.pile noise打桩噪音 40.pile rig打桩机九. 固结consolidation1.Terzzaghi’s consolidation theory太沙基固结理论2.Barraon’s consolidation theory巴隆固结理论3.Biot’s consolidation theory比奥固结理论4.over consolidation ration (OCR)超固结比5.overconsolidation soil超固结土6.excess pore water pressure超孔压力7.multi-dimensional consolidation多维固结8.one-dimensional consolidation一维固结9.primary consolidation主固结10.secondary consolidation次固结11.degree of consolidation固结度 12.consolidation test固结试验 13.consolidation curve固结曲线 14.time factor Tv时间因子15.coefficient of consolidation固结系数16.preconsolidation pressure前期固结压力17.principle of effective stress有效应力原理18.consolidation under K0 condition K0固结十. 抗剪强度shear strength 1.undrained shear strength不排水抗剪强度2.residual strength剩余强度3.long-term strength长期强度4.peak strength峰值强度5.shear strain rate剪切应变速率6.dilatation剪胀7.effective stress approach of shear strength 剪胀抗剪强度有效应力法 8.total stress approach of shear strength抗剪强度总应力法 9.Mohr-Coulomb theory莫尔－库仑理论 10.angle of internal friction内摩擦角 11.cohesion粘聚力 12.failure criterion破坏准那么 13.vane strength十字板抗剪强度14.unconfined compression无侧限抗压强度15.effective stress failure envelop有效应力破坏包线16.effective stress strength parameter有效应力强度参数十一. 本构模型--constitutive model1.elastic model弹性模型2.nonlinear elastic model非线性弹性模型3.elastoplastic model弹塑性模型4.viscoelastic model粘弹性模型5.boundary surface model边界面模型6.Duncan-Chang model邓肯－张模型7.rigid plastic model 刚塑性模型8.cap model盖帽模型9.work softening加工软化 10.work hardening加工硬化 11.Cambridge model剑桥模型 12.ideal elastoplastic model理想弹塑性模型 13.Mohr-Coulomb yield criterion莫尔－库仑屈服准那么14.yield surface屈服面15.elastic half-space foundation model弹性半空间地基模型 16.elastic modulus弹性模量 17.Winkler foundation model 文克尔地基模型十二. 地基承载力--bearing capacity of foundation soil 1.punching shear failure冲剪破坏 2.general shear failure整体剪切破化 3.local shear failure局部剪切破坏 4.state of limit equilibrium极限平衡状态5.critical edge pressure临塑荷载6.stability of foundation soil地基稳定性7.ultimate bearing capacity of foundation soil地基极限承载力 8.allowable bearing capacity of foundation soil地基容许承载力十三. 土压力--earth pressure1.active earth pressure主动土压力2.passive earth pressure 被动土压力3.earth pressure at rest静止土压力4.Coulomb’s earth pressure theory库仑土压力理论5.Rankine’s earth pressure theory朗金土压力理论十四. 土坡稳定分析--slope stability analysis1.angle of repose休止角2.Bishop method毕肖普法3.safety factor of slope边坡稳定平安系数4.Fellenius method of slices费纽伦斯条分法5.Swedish circle method瑞典圆弧滑动法6.slices method 条分法十五. 挡土墙--retaining wall1.stability of retaining wall挡土墙稳定性2.foundation wall根底墙3.counter retaining wall扶壁式挡土墙4.cantilever retaining wall悬臂式挡土墙5.cantilever sheet pile wall悬臂式板桩墙6.gravity retaining wall重力式挡土墙7.anchored plate retaining wall锚定板挡土墙8.anchored sheet pile wall锚定板板桩墙十六. 板桩结构物--sheet pile structure 1.steel sheet pile钢板桩 2.reinforced concrete sheet pile钢筋混凝土板桩 3.steel piles钢桩 4.wooden sheet pile木板桩 5.timber piles木桩十七. 浅根底--shallow foundation 1.box foundation箱型根底 2.mat(raft) foundation片筏根底 3.strip foundation条形根底 4.spread footing扩展根底 5 pensated foundation补偿性根底 6.bearing stratum持力层 7.rigid foundation刚性根底 8.flexible foundation柔性根底9.embedded depth of foundation根底埋置深度 foundation pressure基底附加应力11.structure-foundation-soil interaction analysis上部结构－根底－地基共同作用分析十八. 土的动力性质--dynamic properties of soils1.dynamic strength of soils动强度2.wave velocity method 波速法3.material damping材料阻尼4.geometric damping 几何阻尼5.damping ratio阻尼比6.initial liquefaction初始液化7.natural period of soil site地基固有周期8.dynamic shear modulus of soils动剪切模量 9.dynamic ma 二十. 地基根底抗震1.earthquake engineering地震工程 2.soil dynamics土动力学 3.duration of earthquake地震持续时间 4.earthquake response spectrum地震反响谱 5.earthquake intensity地震烈度 6.earthquake magnitude 震级 7.seismic predominant period地震卓越周期 8.maximum acceleration of earthquake地震最大加速度二十一. 室内土工实验 1.high pressure consolidation test高压固结试验 2.consolidation under K0 condition K0固结试验 3.falling head permeability变水头试验4.constant head permeability常水头渗透试验5.unconsolidated-undrained triaxial test不固结不排水试验(UU)6.consolidated undrained triaxial test固结不排水试验(CU)7.consolidated drained triaxial test固结排水试验(CD)8 paction test击实试验9.consolidated quick direct shear test固结快剪试验10.quick direct shear test快剪试验11.consolidated drained direct shear test慢剪试验12.sieve analysis筛分析 13.geotechnical model test土工模型试验 14.centrifugalmodel test离心模型试验15.direct shear apparatus直剪仪 16.direct shear test直剪试验 17.direct simple shear test直接单剪试验18.dynamic triaxial test三轴试验 19.dynamic simple shear动单剪 20.free〔resonance〕vibration column test自(共)振柱试验二十二. 原位测试1.standard penetration test (SPT)标准贯入试验 2.surface wave test (SWT)外表波试验 3.dynamic penetration test(DPT)动力触探试验 4.static cone penetration (SPT) 静力触探试验 5.plate loading test静力荷载试验 teral load test of pile 单桩横向载荷试验 7.static load test of pile 单桩竖向荷载试验 8.cross-hole test 跨孔试验 9.screw plate test螺旋板载荷试验 10.pressuremeter test旁压试验 11.light sounding轻便触探试验 12.deep settlement measurement深层沉降观测 13.vane shear test十字板剪切试验 14.field permeability test现场渗透试验 15.in-situ pore water pressure measurement 原位孔隙水压量测 16.in-situ soil test原位试验。
土木工程外文翻译(中英互译版)
使用加固纤维聚合物增强混凝土梁的延性Nabil F. Grace, George Abel-Sayed, Wael F. Ragheb摘要：一种为加强结构延性的新型单轴柔软加强质地的聚合物(FRP)已在被研究，开发和生产(在结构测试的中心在劳伦斯技术大学)。
这种织物是两种碳纤维和一种玻璃纤维的混合物，而且经过设计它们在受拉屈服时应变值较低，从而表达出伪延性的性能。
通过对八根混凝土梁在弯曲荷载作用下的加固和检测对研制中的织物的效果和延性进行了研究。
用现在常用的单向碳纤维薄片、织物和板进行加固的相似梁也进行了检测，以便同用研制中的织物加固梁进行性能上的比拟。
这种织物经过设计具有和加固梁中的钢筋同时屈服的潜力，从而和未加固梁一样，它也能得到屈服台阶。
相对于那些用现在常用的碳纤维加固体系进行加固的梁，这种研制中的织物加固的梁承受更高的屈服荷载，并且有更高的延性指标。
这种研制中的织物对加固机制表达出更大的奉献。
关键词：混凝土，延性，纤维加固，变形介绍外贴粘合纤维增强聚合物〔FRP〕片和条带近来已经被确定是一种对钢筋混凝土结构进行修复和加固的有效手段。
关于应用外贴粘合FRP板、薄片和织物对混凝土梁进行变形加固的钢筋混凝土梁的性能，一些试验研究调查已经进行过报告。
Saadatmanesh和Ehsani〔1991〕检测了应用玻璃纤维增强聚合物(GFRP)板进行变形加固的钢筋混凝土梁的性能。
Ritchie等人〔1991〕检测了应用GFRP，碳纤维增强聚合物〔CFRP〕和G/CFRP板进行变形加固的钢筋混凝土梁的性能。
Grace等人〔1999〕和Triantafillou〔1992〕研究了应用CFRP薄片进行变形加固的钢筋混凝土梁的性能。
Norris，Saadatmanesh和Ehsani〔1997〕研究了应用单向CFRP薄片和CFRP织物进行加固的混凝土梁的性能。
在所有的这些研究中，加固的梁比未加固的梁承受更高的极限荷载。
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。
Earthquake Resistant Structural Systems -土木工程外文翻译
Earthquake Resistant Structural Systems -土木工程外文翻译3Building Engineering Ⅱ: Building Structures and SeismicResistance3.1Text3.1.1PassageEarthquake ResistantStructural Systems1Rigid Frame StructuresRigid frame structures typically comprise floor diaphragms supported on beams which link to continuous columns (Figure 3-1). The joints between beam and columns are usually considered to be “rigid”. The frames are expected to carry the gravity loads through the flexural action of the beams and the prop ping action of the columns. Negative moments are induced in the beam adjacent to the columns causing the mid-span positive moment to be significantly less than in a simply supported span. In structures in which gravity loads dictate the design, economies in member size that arise from this effect tend to be offset by the higher cost of the rigid joints.Figure 3-1 Rigidframe structureLateral loads, imposed within the plane of the frame, are resisted through the development of bending moments in the beams and columns. Framed buildings often employ moment resistant frames in two orthogonal directions, in which case the column elements are common to both frames.Rigid frame structures are well suited to accommodate high levels of inelastic deformation. When a capacity design approach is employed, it is usual to assign the end zones of the flexural beams to accept the post-elastic deformation expected, and to design the column members such that their dependable strength is in excess of the over-strength capacity of the beam hinges, thereby ensuring they remain within their elastic response range regardless of the intensity of ground shaking. Rigid frame structures are, however, often quite flexible. When they aredesigned to be fully ductile, special provisions are often needed to prevent the premature onset of damage to non-structural components.Rigid frame construction is ideally suited for reinforced concrete building because of the inherent rigidity of reinforced concrete joints. The rigid frame form is also used for steel framebuildings. But moment resistant connections in steel tend to be costly. The sizes of the columns and girders at any level of a rigid-frame are directly influenced by the magnitude of the external shear at that level, and they therefore increase toward the base. Consequently, the design of the floor framing can not be repetitive as it is in some braced frames. A further result is that sometimes it is not possible in the lowest storeys to accommodate the required depth of girder within the normal ceiling space.While rigid frames of a typical scale that serve alone to resist lateral loading have an economic height limit of about 25 storeys, smaller scale rigid frames in the form of a perimeter tube, or typically scaled rigid frames in combination with shear walls or braced bents, can be economic up to much greater heights.2Infilled Frame StructuresInfilled frames (Figure 3-2) are the most usual form of construction for tall buildings of up to 30 storeys in height. Column and girder framing of reinforced concrete, or sometimes steel, is infilled by panels of brickwork, or cast-in-place concrete.Figure 3-2 InfilledframeWhen an infilled frame is subjected to lateral loading, the infill behaves effectively as a strut along its compression diagonal to brace the frame. Because the infills serve also as external walls or internal partitions, the system is an economical way of stiffening and strengthening the structure.The complex interactive behavior of the infill in the frame, and the rather random quality of masonry, had made it difficult to predicate with accuracy the stiffness and strength of an infilled frame. For these reasons, the use of the infills for bracing buildings has mainly been supplementary to the rigid frame action of concrete frames.3Shear WallsA shear wall is a vertical structural element that resists lateral forces in the plane of the wall through shear and bending. The high in planstiffness and strength of concrete and masonry walls make them ideally suitable for bracing building as shear walls.A shear wall acts as a beam cantilevered out of the ground or foundation9 and, just as with a beam, part of its strength derives from its depth. Figure 3-3 shows two examples of a shear wall, one in a simple one-storey building and another in a multistorey building. In Figure 3-3a, the shear walls are oriented in one direction, so only lateral forces in this direction can be resisted. The roof serves as the horizontal diaphragm and must also be designed to resist the lateral loads and transfer them to the shear walls.a) End shear walls and interior shear wall b)Interior shear walls forbracing in two directionFigure 3-3 Shear wallFigure 3-3a also shows an important aspect of shear walls in particular and vertical elements in general. This is the aspect of symmetry that has a bearing on whether torsional effects will be produced. The shear walls in Figure 3-3a show the shear walls symmetrical in the plane of loading.Figure 3-3b illustrates a common use of shear walls at the interior of a multi-storey building. Because walls enclosing stairways, elevator shafts, and mechanical chases are mostly solid and run the entire height of the building, they are often used for shear walls. Although not as efficient from a strictly structural point of view, interior shear walls do leave the exterior of the building open for windows.Notice that in Figure 3-3b there are shear walls in both directions, which is a more realistic situation because both wind and earthquake forces need to be resisted in both directions. In this diagram, the two shear walls are symmetrical in one direction, but the single shear wall produces a nonsymmetric condition in the other since it is off center. Shear walls do not need to be symmetrical in a building, but symmetry is preferred to avoid torsional effects. If, in low-to medium-rise building, shear walls are combined with frames, it is reasonable to assume that the shear wall attract all the lateral loading so that the frame may be designed for only gravity loading. It is essentially important in shear wall structures to try to plan the wall layout so that the lateral load tensile stresses are suppressed by the gravity load stresses. This allows them to be designed to have only the minimum reinforcement.Since shear walls are generally both stiff and can be inherently robust, it is practical to design them to remain nominally elastic under design intensity loadings, particularly in regions of low or moderate seismicity. Under increased loadingintensities, post-elastic deformations will develop within the lower portion of the wall (generally considered to extend over a height of twice the wall length above the foundation support system).Good post-elastic response can be readilyachieved within this region of reinforced concrete or masonry shear walls through the provision of adequate confinement of the principal reinforcing steel and the prohibition oflap splices of reinforcing bars. Shear wall structures are generally quite stiff and, as such interstorey drift problems are rare and generally easily contained. The shear wall tends to act as a rigid body rotating about a plastic hinge which forms at the base of the wall. Overall structural deformation is thus a function of the wall rotation. Inter-storey drift problems which do occur are limited to the lower few floors.A major shortcoming with shear walls within buildings is that their size provides internal (or external) access barriers which may contravene the architectural requirements. This problem canbe alleviated by coupling adjacent more slender shear walls so a coupled shear wall structure is formed. The coupling beams then become shear links between the two walls and with careful detailing can provide a very effective, ductile control mechanism (Figure 3-4).Figure 3-4 Coupled shear wallstructure4Braced FramesA braced frame is a truss system of the concentric or eccentric type in which the lateral forces are resisted through axial stresses in the members. Just as with a truss, the braced frame depends on diagonal members to provide a load path for lateral forces from each building element to the foundation. Figure 3-5 shows a simple one-storey braced frame. At one end of the building two bays are braced and at the other end only one bay is braced. This building is only braced in one direction and the diagonal member may be either in tension or compression,depending on which way the force is applied.a)Single story braced buildingb) Multistory bracedbuilding Figure 3-5Braced frameFigure 3-5b shows two methods of bracing a multistorey building. A single diagonal compression member in one bay can be used to brace against lateral loads coming from either direction. Alternately, tension diagonals can be used to accomplish the same result, but they must be run both ways to account for the load coming from either direction.Braced framing can be placed on the exterior or interior of a building, and may be placed in one structural bay or several. Obviously, a braced frame can present design problems for windows and doorways, but it is a very efficientand rigid lateral force resisting system.Two major shortcomings of braced systems are that their inclined diagonal orientation oftenconflicts with conventional occupancy use patterns; and secondly they often require careful detailing to avoid large local torsional eccentricities being introduced at the connections with the diagonal brace being offset from the frame node.5Wall-frame StructuresWhen shear walls are combined with rigid frames (Figure 3-6), the walls, which tend to deflect in a flexural configuration, and the frames, which tend to deflect in a shear mode, are constrained to adopt a common shape by the horizontal rigidity of the girders and slabs. As a consequence, the walls and frames interact horizontally, especially at the top, to produce a stiffer and stronger structure. The interacting wall-frame combination is appropriate for buildings in the 40-to-60-storey range, well beyond of rigid frame or shear wall alone.Figure 3-6Wall-frame structureIn addition, less well-known feature of the wall- frame structure is that, in a carefully “tuned” structure, the shear in the frame can be made approximately uniform over the height, allowing the floor framing to be repetitive. Although the wall-frame structure is usually perceived as a concrete structural form, with shear walls and concrete frames, a steel counterpart using braced frames and steel rigid frames offers similar benefit of horizontal interaction. The braced frames behave with an overall flexural tendency to interact with the shear mode of the rigid frames.6Framed-Tube StructuresThe lateral resistance of framed-tube structures is provided by very stiff moment resisting frames that form a “tube” around the perimeter of the building. The frames consist of closely spaced column, 2~4m between centers, joined by deep spandrel girders (Figure 3-7). Although the tube carries all the lateral loading, the gravity load is shared between the tube and interior columns or walls. When lateral loading acts, the perimeter frames aligned in thedirection of loading act as the “web” of the massive tube cantilever, and those normal to the direction of the loading act as the “flanges”.Figure 3-7Frame-tube structureThe close spacing of the columns throughout the height of the structures is usually unacceptable at the entrance level. The columns are therefore merged, or terminated on a transfer beam, a few storeys above the base so that only a few, larger, more widely spaced columns continue to the base. The tube form was developed originally for buildings of rectangular plan; however, for other plan shapes, and has occasionally been used in circular and triangular configurations.The tube is suitable for both steel and reinforced construction and has been used for buildings ranging from 40 to more storeys. The highly repetitive pattern of the frames lends itself to prefabrication in steel, and to the use of rapidly gang forms in concrete, which make for rapid construction.The framed tube has been one of the most significant modern developments in high-rise structural form. It offers a relatively efficiently, easily constructed structure, appropriate for use up to the greatest of heights. Aesthetically, the tube’s externally evident form is regarded with mixed enthusiasm: some praise the logical clearly expressed structure while others criticize the girder-like façade as small-windowed and uninteresting repetitious.The tube structure’s structural efficiency, although high, still leaves scope for improvement because the “flange” frames tend to suffer from “shear lag”; this result in mid-face “flange” columns being less stresses than the corner columns and, therefore, not contributing as fully as they could to the flange action.7Tube-in-Tube or Hull-Core StructuresThis variation of the framed tube consists of an outer framed tube, the “hull” together with an internal elevator and service core (Figure 3-8). The hull and the inner core act jointly in resisting both gravity and lateral loading. In a steel structure the core may consist of braced frames, whereas in a concrete structure it wouldconsist of an assembly of shear walls.Figure 3-8Tube-in-tubeTo some extent, the outer framed tube and the inner core interact horizontally as the shear and flexural components of a wall-frame structure, with the benefit of increase lateral stiffness. However, the structural tube usually adopts a highly dominant role because of its much greater structural depth.8Braced-Tube StructuresAnother way of improving the efficiency of the framed tube, thereby increasing its potential for greater heights as well as allowing greater spacing between the columns, is to add diagonal bracing to the faces of the tube. This arrangement was first used in a steel structure in 1969, in Chicago’s John Hancock Building (Figure 3-9). Because the diagonal of a braced tube are connected to the columns at each intersection, they virtually eliminate the effects of shear lag in both the flange and web frames.As a result, the structure behaves under lateral loading more like a braced frame, with greatly diminished bending in the members of the frames. Consequently, the spacing of the columns can be larger and the depth of the spandrels less, thereby allowing larger size windows than in the conventional tube structure.Figure 3-9Braced-TubeStructuresIn the braced-tube structure the bracing contributes also to the improved performance of the tube in carrying gravity loading: differences between gravity load stresses in the columns are evened out by the braces transferring loading from the more highly to the less highly stressed columns.9Bundled-Tube StructuresThis structural form has been used for the Sears Tower in Chicago. The Sears Tower consists of four parallel rigid steel frames in each orthogonal direction, interconnected to form nine “bundled” tubes. As in the single-tube structure, the frames in the direction of lateral loading serves as “webs” of the vertical cantilever, with the normal frame acting as “flanges”.The introduction of internal webs greatly reduces the shear lag in the flanges; consequently their columns are more evenly stressed than in the single-tube structure, and their contribution to the lateral stiffness is great. This allows columns of the frames to be spaced further apart and to be less obtrusive. In the Sears Tower, advantage was taken of the bundled form to discontinue some of the tubes, and so reduce the plan of the building at stages up to the height.3.1.2New Words and Expressionsbraced frame支撑框架braced-tube桁架筒bundled-tube束筒couplingbeam 连梁coupledshear wall 联肢墙framedtube 框筒inter-storeydrift 层间位移propping[ 'prɔpiŋ ] n. 支撑rigid frame框架shear lag 剪力滞后spandrel [ 'spændrəl ] n.上下层窗间墙stairway [ 'stεəwei ] n.楼梯transfer beam 转换粱tube-in-tube / hull-core 筒中筒wall-frame structure 框架-剪力墙结构3.1.3Exercises1Please name the types of earthquake resistant structural systems.2How does a rigid frame structureresist the gravity load and lateralload? 3 Why are shear walls in both directions preferred?4 How are the loads shared between frame and tube in a framed-tube structure?3.2Reading Materials3.2.1Passage OneReinforced ConcreteStructuresConcrete 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 thewide 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.1Mechanics of Reinforced Concrete Concrete is strong in compression but weak in tension. As a result, cracks develop whenever loads, or restrained shrinkage or temperature changes, give rise to tensile stresses in excess of the tensile strength of the concrete. In the plain concrete beam, the moments 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 form or mold in the shape of the member being built. The form must be strong enough to support 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 place during the concreting operation. After the concrete has hardened, the forms are removed.2Factors Affecting Choice of Concrete for aStructureThe 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.(1)EconomyFrequently, the foremost consideration is the overall cost 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 allocate money to carry out the construction and will not receive a return on this investment until the building isready for occupancy. As a result, financial savings due to rapid construction may more than offset increased material costs. 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 considerations.(2)Suitability of Material for Architectural andStructural FunctionA 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 shape and texture by means of the forms and the finishing techniques. This allows such elements as flat plates or other types of slabs to serve as load-bearing elements while providing the finished floor and ceiling surfaces. Similarly, reinforced concrete wails can provide architecturally attractive surfaces in addition to having the ability to resist gravity, wind, or seismic loads. Finally, the choice of size or shape is governed by the designer and not bythe availability of standard manufactured members.(3)Fire ResistanceThe 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 befireproofed to attain similar fire ratings.(4)RigidityThe occupants of a building may be disturbed if their building oscillates in the wind or the floors vibrate as people walk by. Due to the greater stiffness and mass of a concrete structure, vibrations are seldom a problem.(5)Low MaintenanceConcrete 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.(6)Availability of MaterialsSand, 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 StrengthAs stated earlier, the tensile strength of 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.(2)Forms and ShoringThe construction of a cast-in-place structure involves three steps not encountered in the construction of steel or timber structures. These are the construction of the forms, the removal of these forms, and 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 Weightor VolumeThe 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 acomparable steel structure. As a result, long-span structures are often built from steel.(4)Time-dependent Volume ChangesBoth 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 conductor than 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 drying 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.3Building CodesThe first set of building regulations for reinforced concrete were drafted under the leadership of Professor Morsch of the University of Stuttgart and were issued in Prussia in 1904. Design regulations were issued in Britain, France, Austria, and Switzerland between 1907 and 1909.The American Railway Engineering Association appointed a Committee on Masonry in 1890. In 1903 this committee presented specifications for Portland cement concrete. Between 1908 and 1910 a series of committee reports led to the Standard Building Regulations for the Use of Reinforced Concrete published in 1910 by the National Association of Cement Users which subsequently became the American Concrete Institute.A Joint Committee on Concrete and Reinforced Concrete was established in 1904 by the American Society of Civil Engineers, American Society for Testing and Materials, the American Railway Engineering Association, and the Association of American Portland Cement Manufactures. This group was later joined by the American Concrete Institute. Between 1904 and 1910 the Joint Committee carried out research. A preliminary report issued in 1913 lists the more important papers and books on reinforced concrete published between 1898 and 1911. The final report of this committee was published in 1916. The history of reinforced concrete building codes in the United States wasreviewed in 1954 by Kerekes and Reid.The design and construction of buildings is regulated by municipal bylaws called building codes. These exist to protect the public health and safety. Each city and town is free to write or adopt its own building code, and in that city or town, only that particular code has legal status. Because of the complexity of building code writing, cities in the United States generally base their building codes on one of three model codes: the Uniform Building Code, the Standard Building Code, or the Basic Building Code. These codes cover such things as use and occupancy requirements, fire requirements, heating and ventilating requirements, and structural design.The definitive design specification for reinforced concrete buildings in North America is the Building Code Requirements for Reinforced Concrete (ACI-318-95), which is explained in a Commentary.This code, generally referred to as the ACI Code, has been incorporated in most building codes in the United States and serves as the basis for comparable codes in Canada, New Zealand,Australia, and parts of Latin America. The ACI Code has legal status only if adopted in a local building code.Each nation or group of nations in Europe has its own building code for reinforced concrete. The CEB-FIP Model Code for Concrete Structures is intended to serve as the basis for future attempts to unify European codes. This code and the ACI Code are similar in many ways.3.2.2Passage TwoEarthquake Induced Vibration ofStructures1Seismicity and Ground MotionsThe most common cause of earthquakes is thought to be the violent slipping of rock masses along major geological fault lines in the Earth’s crust, or lithosphere. These fault lines divide the global crust into about 12 major tectonic plates, which are rigid, relatively cool slabs about 100km thick. Tectonic plates float on the molten mantle of the Earth and move relative to one another at the rate of 10 to 100mm/year.The basic mechanism causing earthquakes inthe plate boundary regions appears to be that the continuing deformation of the crustal structure eventually leads to stresses which exceed the material strength. A rupture will then initiate at some critical point along the fault line and willpropagate rapidly through the highly stressed material at the plate boundary. In some cases, the plate margins are moving away from one another. In those cases, molten rock appears from deep in the Earth to fill the gap, often manifesting itself as volcanoes. If the plates are pushing together, one plate tends to dive under the other and, depending on the density of the material, it may resurface in the form of mountains and valleys. In both these scenarios, there may be volcanoes and earthquakes at the plate boundaries, both being caused by the same mechanism of movement in the Earth's crust. Another possibility is that the plate boundaries will slide sideways past each other, essentially retaining the local surface area of the plate. It is believed that about three quarters of the world's earthquakes are accounted for by this rubbing-striking-slipping mechanism, with ruptures occurring on faults on boundaries between tectonic plates. Earthquake occurrence maps tend to outline the plate boundaries. Such earthquakes are referred to as interplate earthquakes.Earthquakes also occur at locations away。
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 loadsCommonly 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 thestructural 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 in conjunction 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 narrowoverturning, 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 wall in 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 overturning 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 (i.e, the webs of the framed tube) while the flexural component is associated with the axial shortening and lengthening of columns (i.e, 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 (i.e, 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 even higher, 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 (i.e, shear-stiff) tube while the outer tube is conceived as a framed (i.e, 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% sti ffer 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 shear stiffness 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 (28.6m) wide, 196ft(59.7m) long, and 601ft (183.3m) high.2.Two inner tubes are provided, each 31ft(9.4m) by 40 ft (12.2m), centered 90 ft (27.4m) apart in the long direction of thebuilding.3.The inner tubes are braced in the short direction, but with zero shear stiffness in the long direction.4. A single outer tube is supplied, which encircles the building perimeter.5.The outer tube is a moment-resisting frame, but with zero shear stiffness for the center50ft (15.2m) of each of the longsides.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 twin steel-plate tubes, because the shear stiffness of the outertube 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 Tower contains 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 (3.66m) floor-to-floor distances and an average compressive stress of 15 ksi (138MPa), the shortening of a column under load is 15 (12)(12)/29,000 or 0.074in (1.9mm) per story. At 50 stories, the column will have shortened to 3.7 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 simulating the 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。
土木工程专业外文翻译--桩基础
外文原文1.1 Pile foundationsPile foundations [11] are the part of a structure used to carry and transfer the load of the structure to the bearing ground located at some depth below ground surface. The main components of the foundation are the pile cap and the piles. Piles are long and slender members which transfer the load to deeper soil or rock of high bearing capacity avoiding shallow soil of low bearing capacity The main types of materials used for piles are Wood, steel and concrete. Piles made from these materials are driven, drilled or jacked into the ground and connected to pile caps. Depending upon type of soil, pile material and load transmitting characteristic piles are classified accordingly. In the following chapter we learn about, classifications, functions and pros and cons of piles.1.2 HistoricalIn the early days of civilisation[2], from the communication, defence or strategic point of view villages and towns were situated near to rivers and lakes. It was therefore important to strengthen the bearing ground with some form of piling.Timber piles were driven in to the ground by hand or holes were dug and filled with sand and stones.In 1740 Christoffoer Polhem invented pile driving equipment which resembled to days pile driving mechanism. Steel piles have been used since 1800 and concrete piles since about 1900.The industrial revolution brought about important changes to pile driving system through the invention of steam and diesel driven machines.More recently, the growing need for housing and construction has forced authorities and development agencies to exploit lands with poor soil characteristics. This has led to the development and improved piles and pile driving systems. Today there are many advanced techniques of pile installation.1.3 Function of pilesAs with other types of foundations, the purpose of a pile foundations is:to transmit a foundation load to a solid ground to resist vertical, lateral and uplift load.A structure can be founded on piles if the soil immediately beneath its base does not have adequate bearing capacity. If the results of site investigation show that the shallow soil is unstable and weak or if the magnitude of the estimated settlement is not acceptable a pile foundation may become considered. Further, a cost estimate may indicate that a pile foundation may be cheaper than any other compared ground improvement costs.In the cases of heavy constructions, it is likely that the bearing capacity of the shallow soil will not be satisfactory, and the construction should be built on pile foundations. Piles can also be used in normal ground conditions to resist horizontal loads. Piles are a convenient method of foundation for works over water, such as jetties or bridge piers.1.4 Classification of piles1.4.1 Classification of pile with respect to load transmission and functional behaviourEnd bearing piles (point bearing piles)Friction piles (cohesion piles )Combination of friction and cohesion piles1.4.2 End bearing pilesThese piles transfer their load on to a firm stratum located at a considerable depth below the base of the structure and they derive most of their carrying capacity from the penetration resistance of the soil at the toe of the pile (see figure 1.1). The pile behaves as an ordinary column and should be designed as such. Even in weak soil a pile will not fail by buckling and this effect need only be considered if part of the pile is unsupported, i.e. if it is in either air or water. Load is transmitted to the soil through friction or cohesion. But sometimes, the soil surrounding the pile may adhereto the surface of the pile and causes "Negative Skin Friction" on the pile. This, sometimes have considerable effect on the capacity of the pile. Negative skin friction is caused by the drainage of the ground water and consolidation of the soil. The founding depth of the pile is influenced by the results of the site investigate on and soil test.1.4.3 Friction or cohesion pilesCarrying capacity is derived mainly from the adhesion or friction of the soil in contact with the shaft of the pile (see fig 1.2).Figure 1-1 End bearing piles Figure 1-2 Friction or cohesion pile 1.4.4 Cohesion pilesThese piles transmit most of their load to the soil through skin friction. This process of driving such piles close to each other in groups greatly reduces the porosity and compressibility of the soil within and around the groups. Therefore piles of this category are some times called compaction piles. During the process of driving the pile into the ground, the soil becomes moulded and, as a result loses some of its strength. Therefore the pile is not able to transfer the exact amount of load which it is intended to immediately after it has been driven. Usually, the soil regains some of its strength three to five months after it has been driven.These piles also transfer their load to the ground through skin friction. The process of driving such piles does not compact the soil appreciably. These types of pile foundations are commonly known as floating pile foundations.1.4.6 Combination of friction piles and cohesion pilesAn extension of the end bearing pile when the bearing stratum is not hard, such as a firm clay. The pile is driven far enough into the lower material to develop adequate frictional resistance. A farther variation of the end bearing pile is piles with enlarged bearing areas. This is achieved by forcing a bulb of concrete into the soft stratum immediately above the firm layer to give an enlarged base. A similar effect is produced with bored piles by forming a large cone or bell at the bottom with a special reaming tool. Bored piles which are provided with a bell have a high tensile strength and can be used as tension piles (see fig.1-3)Figure 1-3 under-reamed baseenlargement to a bore-and-cast-in-situpile1.4.7 Classification of pile with respect to type of material•Timber•Concrete•Steel•Composite piles[12]Used from earliest record time and still used for permanent works in regions where timber is plentiful. Timber is most suitable for long cohesion piling and piling beneath embankments. The timber should be in a good condition and should not have been attacked by insects. For timber piles of length less than 14 meters, the diameter of the tip should be greater than 150 mm. If the length is greater than 18 meters a tip with a diameter of 125 mm is acceptable. It is essential that the timber is driven in the right direction and should not be driven into firm ground. As this can easily damage the pile. Keeping the timber below the ground water level will protect the timber against decay and putrefaction. To protect and strengthen the tip of the pile, timber piles can be provided with toe cover. Pressure creosoting is the usual method of protecting timber piles.1.4.9 Concrete pilePre cast concrete Piles or Pre fabricated concrete piles : Usually of square (see fig 1-4 b), triangle, circle or octagonal section, they are produced in short length in one metre intervals between 3 and 13 meters. They are pre-caste so that they can be easily connected together in order to reach to the required length (fig 1-4 a) . This will not decrease the design load capacity. Reinforcement is necessary within the pile to help withstand both handling and driving stresses. Pre stressed concrete piles are also used and are becoming more popular than the ordinary pre cast as less reinforcement is required .Figure 1-4 a) concrete pile connecting detail. b) squared pre-cast concert pileThe Hercules type of pile joint (Figure 1-5) is easily and accurately cast into the pile and is quickly and safely joined on site. They are made to accurate dimensional tolerances from high grade steels.Figure 1-5 Hercules type of pile joint1.4.10 Driven and cast in place Concrete pilesTwo of the main types used in the UK are: West’s shell pile : Pre cast, reinforced concrete tubes, about 1 m long, are threaded on to a steel mandrel and driven into the ground after a concrete shoe has been placed at the front of the shells. Once the shells have been driven to specified depth the mandrel is withdrawn and reinforced concrete inserted in the core. Diameters vary from 325 to 600 mm.Franki Pile: A steel tube is erected vertically over the place where the pile is to be driven, and about a metre depth of gravel is placed at the end of the tube. A drop hammer, 1500 to 4000kg mass, compacts the aggregate into a solid plug which then penetrates the soil and takes the steel tube down with it. When the required depth hasbeen achieved the tube is raised slightly and the aggregate broken out. Dry concrete is now added and hammered until a bulb is formed. Reinforcement is placed in position and more dry concrete is placed and rammed until the pile top comes up to ground level.1.4.11 Steel pilesSteel piles: (figure 1.4) steel/ Iron piles are suitable for handling and driving in long lengths. Their relatively small cross-sectional area combined with their high strength makes penetration easier in firm soil. They can be easily cut off or joined by welding. If the pile is driven into a soil with low pH value, then there is a risk of corrosion, but risk of corrosion is not as great as one might think. Although tar coating or cathodic protection can be employed in permanent works.It is common to allow for an amount of corrosion in design by simply over dimensioning the cross-sectional area of the steel pile. In this way the corrosion process can be prolonged up to 50 years. Normally the speed of corrosion is 0.2-0.5 mm/year and, in design, this value can be taken as 1mm/yeara) X- cross-section b) H - cross-section c) steel pipeFigure 1-6 Steel piles cross-sections1.4.12 Composite pilesCombination of different materials in the same of pile. As indicated earlier, part of a timber pile which is installed above ground water could be vulnerable to insect attack and decay. To avoid this, concrete or steel pile is used above the ground water level, whilst wood pile is installed under the ground water level (see figure 1.7).Figure 1-7 Protecting timber piles from decay:a) by pre-cast concrete upper section above water level.b) by extending pile cap below water level1.4.13 Classification of pile with respect to effect on the soilA simplified division into driven or bored piles is often employed.1.4.14 Driven pilesDriven piles are considered to be displacement piles. In the process of driving the pile into the ground, soil is moved radially as the pile shaft enters the ground. There may also be a component of movement of the soil in the vertical direction.1.4.15 Bored pilesBored piles(Replacement piles) are generally considered to be non-displacement piles a void is formed by boring or excavation before piles is produced. Piles can be produced by casting concrete in the void. Some soils such as stiff clays are particularly amenable to the formation of piles in this way, since the bore hole walls do not requires temporary support except cloth to the ground surface. In unstableground, such as gravel the ground requires temporary support from casing or bentonite slurry. Alternatively the casing may be permanent, but driven into a hole which is bored as casing is advanced. A different technique, which is still essentially non-displacement, is to intrude, a grout or a concrete from an auger which is rotated into the granular soil, and hence produced a grouted column of soil.There are three non-displacement methods: bored cast- in - place piles, particularly pre-formed piles and grout or concrete intruded piles.The following are replacement piles:AugeredCable percussion drillingLarge-diameter under-reamedTypes incorporating pre caste concrete uniteDrilled-in tubesMini piles1.5 Aide to classification of pilesFor a quick understanding of pile classification, a hierarchical representation of pile types can be used. Also advantage and disadvantages of different pile materials is given in section 1.6.1.6 Advantages and disadvantages of different pile materialWood pilesThe piles are easy to handle;Relatively inexpensive where timber is plentiful;Sections can be joined together and excess length easily removed;The piles will rot above the ground water level. Have a limited bearing capacity;Can easily be damaged during driving by stones and boulders;The piles are difficult to splice and are attacked by marine borers in salt water;Prefabricated concrete piles (reinforced) and pre stressed concrete piles. (driven) affected by the ground water conditions;Do not corrode or rot;Are easy to splice. Relatively inexpensive;The quality of the concrete can be checked before driving;Stable in squeezing ground, for example, soft clays, silts and peats pile material can be inspected before piling;Can be re driven if affected by ground heave. Construction procedure unaffected by ground water;Can be driven in long lengths. Can be carried above ground level, for example, through water for marine structures;Can increase the relative density of a granular founding stratum;Relatively difficult to cut;Displacement, heave, and disturbance of the soil during driving;Can be damaged during driving. Replacement piles may be required;Sometimes problems with noise and vibration;Cannot be driven with very large diameters or in condition of limited headroom;Driven and cast-in-place concrete piles;Permanently cased (casing left in the ground);Temporarily cased or uncased (casing retrieved);Can be inspected before casting can easily be cut or extended to the desired length;Relatively inexpensive;Low noise level;The piles can be cast before excavation;Pile lengths are readily adjustable;An enlarged base can be formed which can increase the relative density of a granular founding stratum leading to much higher end bearing capacity;Reinforcement is not determined by the effects of handling or driving stresses;Can be driven with closed end so excluding the effects of GWHeave of neighbouring ground surface, which could lead to re consolidation and the development of negative skin friction forces on piles.Displacement of nearby retaining walls. Lifting of previously driven piles, where the penetration at the toe have been sufficient to resist upward movements.Tensile damage to unreinforced piles or piles consisting of green concrete, where forces at the toe have been sufficient to resist upward movements.Damage piles consisting of uncased or thinly cased green concrete due to the lateral forces set up in the soil, for example, necking or waisting. Concrete cannot be inspected after completion. Concrete may be weakened if artesian flow pipes up shaft of piles when tube is withdrawn.Light steel section or Precast concrete shells may be damaged or distorted by hard driving.Limitation in length owing to lifting forces required to withdraw casing, nose vibration and ground displacement may a nuisance or may damage adjacent structures.Cannot be driven where headroom is limited;Relatively expensive;Time consuming. Cannot be used immediately after the installation;Limited length;Bored and cast in -place (non -displacement piles);Length can be readily varied to suit varying ground conditions;Soil removed in boring can be inspected and if necessary sampled or in- situ test made;Can be installed in very large diameters;End enlargement up to two or three diameters are possible in clays;Material of piles is not dependent on handling or driving conditions;Can be installed in very long lengths;Can be installed with out appreciable noise or vibrations;Can be installed in conditions of very low headroom;No risk of ground heave;Susceptible to "waisting" or "necking" in squeezing ground;Concrete is not placed under ideal conditions and cannot be subsequently inspected;Water under artesian pressure may pipe up pile shaft washing out cement;Enlarged ends cannot be formed in cohesionless materials without special techniques;Cannot be readily extended above ground level especially in river and marine structures;Boring methods may loosen sandy or gravely soils requiring base grouting to achieve economical base resistance;Sinking piles may cause loss of ground I cohesion-less leading to settlement of adjacent structures;Steel piles (Rolled steel section);The piles are easy to handle and can easily be cut to desired length;Can be driven through dense layers. The lateral displacement of the soil during driving is low (steel section H or I section piles) can be relatively easily spliced or bolted;Can be driven hard and in very long lengths;Can carry heavy loads;Can be successfully anchored in sloping rock;Small displacement piles particularly useful if ground displacements and disturbance critical;The piles will corrode;Will deviate relatively easy during driving;Are relatively expensive.Dynamic approachMost frequently used method of estimating the load capacity of driven piles is to use a driving formula or dynamic formula. All such formulae relate ultimate load capacity to pile set (the vertical movement per blow of the driving hammer) and assume that the driving resistance is equal to the load capacity to the pile under staticloading they are based on an idealised representation of the action of the hammer on the pile in the last stage of its embedment.Usually, pile-driving formulae are used either to establish a safe working load or to determine the driving requirements for a required working load.The working load is usually determined by applying a suitable safety factor to the ultimate load calculated by the formula. However, the use of dynamic formula is highly criticised in some pile-design literatures. Dynamic methods do not take into account the physical characteristics of the soil. This can lead to dangerousmiss-interpretation of the results of dynamic formula calculation since they represent conditions at the time of driving. They do not take in to account the soil conditions which affect the long- term carrying capacity, reconsolidation, negative skin friction and group effects.中文译文1.1 桩基础桩基础是结构的一部分，它用来将上部的荷载转承给地表以下一定深度的持力层。
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。
土木工程毕业设计外文翻译最终中英文
7 Rigid-Frame StructuresA rigid-frame high-rise structure typically comprises parallel or orthogonally arranged bents consisting of columns and girders with moment resistant joints. Resistance to horizontal loading is provided by the bending resistance of the columns, girders, and joints. The continuity of the frame also contributes to resisting gravity loading, by reducing the moments in the girders.The advantages of a rigid frame are the simplicity and convenience of its rectangular form.Its unobstructed arrangement, clear of bracing members and structural walls, allows freedom internally for the layout and externally for the fenestration. Rigid frames are considered economical for buildings of up to' about25 stories, above which their drift resistance is costly to control. If, however,a rigid frame is combined with shear walls or cores, the resulting structure is very much stiffer so that its height potential may extend up to 50 stories or more. A flat plate structure is very similar to a rigid frame, but with slabs replacing the girders As with a rigid frame, horizontal and vertical loadings are resisted in a flat plate structure by the flexural continuity between the vertical and horizontal components.As highly redundant structures, rigid frames are designed initially on the basis of approximate analyses, after which more rigorous analyses and checks can be made. The procedure may typically include the following stages:1. Estimation of gravity load forces in girders and columns by approximate method.2. Preliminary estimate of member sizes based on gravity load forces witharbitrary increase in sizes to allow for horizontal loading.3. Approximate allocation of horizontal loading to bents and preliminary analysisof member forces in bents.4. Check on drift and adjustment of member sizes if necessary.5. Check on strength of members for worst combination of gravity and horizontalloading, and adjustment of member sizes if necessary.6. Computer analysis of total structure for more accurate check on memberstrengths and drift, with further adjustment of sizes where required. This stage may include the second-order P-Delta effects of gravity loading on the member forces and drift..7. Detailed design of members and connections.This chapter considers methods of analysis for the deflections and forces for both gravity and horizontal loading. The methods are included in roughly the order of the design procedure, with approximate methods initially and computer techniques later. Stability analyses of rigid frames are discussed in Chapter 16.7.1 RIGID FRAME BEHAVIORThe horizontal stiffness of a rigid frame is governed mainly by the bending resistance of the girders, the columns, and their connections, and, in a tall frame, by the axial rigidity of the columns. The accumulated horizontal shear above any story of a rigid frame is resisted by shear in the columns of that story (Fig. 7.1). The shear causes the story-height columns to bend in double curvature with points of contraflexure at approximately mid-story-height levels. The moments applied to a joint from the columns above and below are resisted by the attached girders, which also bend in double curvature, with points of contraflexure at approximately mid-span. These deformations of the columns and girders allow racking of the frame and horizontal deflection in each story. The overall deflected shape of a rigid frame structure due to racking has a shear configuration with concavity upwind, a maximum inclination near the base, and a minimum inclination at the top, as shown in Fig.7.1.The overall moment of the external horizontal load is resisted in each story level by the couple resulting from the axial tensile and compressive forces in the columns on opposite sides of the structure (Fig. 7.2). The extension and shortening of the columns cause overall bending and associated horizontal displacements of the structure. Because of the cumulative rotation up the height, the story drift dueto overall bending increases with height, while that due to racking tends to decrease. Consequently the contribution to story drift from overall bending may, in. the uppermost stories, exceed that from racking. The contribution of overall bending to the total drift, however, will usually not exceed 10% of that of racking, except in very tall, slender,, rigid frames. Therefore the overall deflected shape of a high-rise rigid frame usually has a shear configuration.The response of a rigid frame to gravity loading differs from a simply connected frame in the continuous behavior of the girders. Negative moments are induced adjacent to the columns, and positive moments of usually lesser magnitude occur in the mid-span regions. The continuity also causes the maximum girder moments to be sensitive to the pattern of live loading. This must be considered when estimating the worst moment conditions. For example, the gravity load maximum hogging moment adjacent to an edge column occurs when live load acts only on the edge span andalternate other spans, as for A in Fig. 7.3a. The maximum hogging moments adjacent to an interior column are caused, however, when live load acts only on the spans adjacent to the column, as for B in Fig. 7.3b. The maximum mid-span sagging moment occurs when live load acts on the span under consideration, and alternate other spans, as for spans AB and CD in Fig. 7.3a.The dependence of a rigid frame on the moment capacity of the columns for resisting horizontal loading usually causes the columns of a rigid frame to be larger than those of the corresponding fully braced simply connected frame. On the other hand, while girders in braced frames are designed for their mid-span sagging moment, girders in rigid frames are designed for the end-of-span resultant hogging moments, which may be of lesser value. Consequently, girders in a rigid frame may be smaller than in the corresponding braced frame. Such reductions in size allow economy through the lower cost of the girders and possible reductions in story heights. These benefits may be offset, however, by the higher cost of the more complex rigid connections.7.2 APPROXIMATE DETERMINATION OF MEMBER FORCES CAUSED BY GRAVITY LOADSIMGA rigid frame is a highly redundant structure; consequently, an accurate analysis can be made only after the member sizes are assigned. Initially, therefore, member sizes are decided on the basis of approximate forces estimated either by conservativeformulas or by simplified methods of analysis that are independent of member properties. Two approaches for estimating girder forces due to gravity loading are given here.7.2.1 Girder Forces—Code Recommended ValuesIn rigid frames with two or more spans in which the longer of any two adjacent spans does not exceed the shorter by more than 20 %, and where the uniformly distributed design live load does not exceed three times the dead load, the girder moment and shears may be estimated from Table 7.1. This summarizes the recommendations given in the Uniform Building Code [7.1]. In other cases a conventional moment distribution or two-cycle moment distribution analysis should be made for a line of girders at a floor level.7.2.2 Two-Cycle Moment Distribution [7.2].This is a concise form of moment distribution for estimating girder moments in a continuous multibay span. It is more accurate than the formulas in Table 7.1, especially for cases of unequal spans and unequal loading in different spans.The following is assumed for the analysis:1. A counterclockwise restraining moment on the end of a girder is positive anda clockwise moment is negative.2. The ends of the columns at the floors above and below the considered girder are fixed.3. In the absence of known member sizes, distribution factors at each joint aretaken equal to 1 /n, where n is the number of members framing into the joint in the plane of the frame.Two-Cycle Moment Distribution—Worked Example. The method is demonstrated by a worked example. In Fig, 7.4, a four-span girder AE from a rigid-frame bent is shown with its loading. The fixed-end moments in each span are calculated for dead loading and total loading using the formulas given in Fig, 7.5. The moments are summarized in Table 7.2.The purpose of the moment distribution is to estimate for each support the maximum girder moments that can occur as a result of dead loading and pattern live loading.A different load combination must be considered for the maximum moment at each support, and a distribution made for each combination.The five distributions are presented separately in Table 7.3, and in a combined form in Table 7.4. Distributions a in Table 7.3 are for the exterior supports A andE. For the maximum hogging moment at A, total loading is applied to span AB with dead loading only on BC. The fixed-end moments are written in rows 1 and 2. In this distribution only .the resulting moment at A is of interest. For the first cycle, joint B is balanced with a correcting moment of - (-867 + 315)/4 = - U/4 assigned to M BA where U is the unbalanced moment. This is not recorded, but half of it, ( - U/4)/2, is carried over to M AB. This is recorded in row 3 and then added to the fixed-end moment and the result recorded in row 4.The second cycle involves the release and balance of joint A. The unbalancedmoment of 936 is balanced by adding -U/3 = -936/3 = -312 to M BA (row 5), implicitly adding the same moment to the two column ends at A. This completes the second cycle of the distribution. The resulting maximum moment at A is then given by the addition of rows 4 and 5, 936 - 312 = 624. The distribution for the maximum moment at E follows a similar procedure.Distribution b in Table 7.3 is for the maximum moment at B. The most severe loading pattern for this is with total loading on spans AB and BC and dead load only on CD. The operations are similar to those in Distribution a, except that the T first cycle involves balancing the two adjacent joints A and C while recording only their carryover moments to B. In the second cycle, B is balanced by adding - (-1012 + 782)/4 = 58 to each side of B. The addition of rows 4 and 5 then gives the maximum hogging moments at B. Distributions c and d, for the moments at joints C and D, follow patterns similar to Distribution b.The complete set of operations can be combined as in Table 7.4 by initially recording at each joint the fixed-end moments for both dead and total loading. Then the joint, or joints, adjacent to the one under consideration are balanced for the appropriate combination of loading, and carryover moments assigned .to the considered joint and recorded. The joint is then balanced to complete the distribution for that support.Maximum Mid-Span Moments. The most severe loading condition for a maximum mid-span sagging moment is when the considered span and alternate other spans and total loading. A concise method of obtaining these values may be included in the combined two-cycle distribution, as shown in Table 7.5. Adopting the convention that sagging moments at mid-span are positive, a mid-span total; loading moment is calculated for the fixed-end condition of each span and entered in the mid-span column of row 2. These mid-span moments must now be corrected to allow for rotation of the joints. This is achieved by multiplying the carryover moment, row 3, at the left-hand end of the span by (1 + 0.5 D.F. )/2, and the carryover moment at the right-hand end by -(1 + 0.5 D.F.)/2, where D.F. is the appropriate distribution factor, and recording the results in the middle column. For example, the carryover to the mid-span of AB from A = [(1 + 0.5/3)/2] x 69 = 40 and from B = -[(1+ 0.5/4)/2] x (-145) = 82. These correction moments are then added to the fixed-end mid-span moment to give the maximum mid-span sagging moment, that is, 733 + 40 + 82 = 855.7.2.3 Column ForcesThe gravity load axial force in a column is estimated from the accumulated tributary dead and live floor loading above that level, with reductions in live loading as permitted by the local Code of Practice. The gravity load maximum column moment is estimated by taking the maximum difference of the end moments in the connected girders and allocating it equally between the column ends just above and below the joint. To this should be added any unbalanced moment due to eccentricity of the girderconnections from the centroid of the column, also allocated equally between the column ends above and below the joint.第七章框架结构高层框架结构一般由平行或正交布置的梁柱结构组成，梁柱结构是由带有能承担弯矩作用节点的梁、柱组成。
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 loadsCommonly 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 developedwithout 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 in conjunction 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 resistlateral 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 wall in 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 (i.e, the webs of the framed tube) while the flexural component is associated with the axial shortening and lengthening of columns (i.e, the flanges of the framed tube). In abraced 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 (i.e, 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 even higher, 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 (i.e, shear-stiff) tube while the outer tube is conceived as a framed (i.e, 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 shear stiffness 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 (28.6m) wide, 196ft(59.7m) long, and 601ft (183.3m) high.2.Two inner tubes are provided, each 31ft(9.4m) by 40 ft (12.2m), centered 90 ft (27.4m)apart in the long direction of the building.3.The inner tubes are braced in the short direction, but with zero shear stiffness in the longdirection.4. A single outer tube is supplied, which encircles the building perimeter.5.The outer tube is a moment-resisting frame, but with zero shear stiffness for the center50ft(15.2m) 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 twin steel-plate tubes, because theshear 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 Tower contains 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 (3.66m) floor-to-floor distances and an average compressive stress of 15 ksi (138MPa), the shortening of a column under load is 15 (12)(12)/29,000 or 0.074in (1.9mm) per story. At 50 stories, the column will have shortened to 3.7 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-stressthe lower height columns so as to reconcile the differential deflections of columns in close proximity with the post-tensioning of the shorter column simulating the 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。
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转型衰退时期的土木工程研究Sergios Lambropoulosa[1], John-Paris Pantouvakisb, Marina Marinellic摘要最近的全球经济和金融危机导致许多国家的经济陷入衰退，特别是在欧盟的周边。
这些国家目前面临的民用建筑基础设施的公共投资和私人投资显著收缩，导致在民事特别是在民用建筑方向的失业。
因此，在所有国家在经济衰退的专业发展对于土木工程应届毕业生来说是努力和资历的不相称的研究，因为他们很少有机会在实践中积累经验和知识，这些逐渐成为过时的经验和知识。
在这种情况下，对于技术性大学在国家经济衰退的计划和实施的土木工程研究大纲的一个实质性的改革势在必行。
目的是使毕业生拓宽他们的专业活动的范围，提高他们的就业能力。
在本文中，提出了土木工程研究课程的不断扩大，特别是在发展的光毕业生的潜在的项目，计划和投资组合管理。
在这个方向上，一个全面的文献回顾，包括ASCE体为第二十一世纪，IPMA的能力的基础知识，建议在其他：显著增加所提供的模块和项目管理在战略管理中添加新的模块，领导行为，配送管理，组织和环境等；提供足够的专业训练五年的大学的研究；并由专业机构促进应届大学生认证。
建议通过改革教学大纲为土木工程研究目前由国家技术提供了例证雅典大学。
1引言土木工程研究（CES）蓬勃发展，是在第二次世界大战后。
土木工程师的出现最初是由重建被摧毁的巨大需求所致，目的是更多和更好的社会追求。
但是很快，这种演变一个长期的趋势，因为政府为了努力实现经济发展，采取了全世界的凯恩斯主义的理论，即公共基础设施投资作为动力。
首先积极的结果导致公民为了更好的生活条件（住房，旅游等）和增加私人投资基础设施而创造机会。
这些现象再国家的发展中尤为为明显。
虽然前景并不明朗（例如，世界石油危机在70年代），在80年代领先的国家采用新自由主义经济的方法（如里根经济政策），这是最近的金融危机及金融危机造成的后果（即收缩的基础设施投资，在技术部门的高失业率），消除发展前途无限的误区。
技术教育的大学所认可的大量研究土木工程部。
旧学校拓展专业并且新的学校建成，并招收许多学生。
由于高的职业声望，薪酬，吸引高质量的学校的学生。
在工程量的增加和科学技术的发展，导致到极强的专业性，无论是在研究还是工作当中。
结构工程师，液压工程师，交通工程师等，都属于土木工程。
试图在不同的国家采用专业性的权利，不同的解决方案，，从一个统一的大学学历和广泛的专业化的一般职业许可证。
这个问题在许多其他行业成为关键。
国际专业协会的专家和机构所确定的国家性检查机构，经过考试后，他们证明不仅是行业的新来者，而且专家通过时间来确定进展情况。
尽管在很多情况下，这些证书虽然没有国家接受，他们赞赏和公认的世界。
在试图改革大学研究（不仅在土木工程）更接近市场需求的过程中，欧盟确定了1999博洛尼亚宣言，它引入了一个二能级系统。
第一级度（例如，一个三年的学士）是进入市场的一个合适的资格。
该宣言的讨论即使在今天，也是广泛、热烈和非决定性的。
然而，应该指出的是，在许多外周少欧美等发达国家的声明是由学术和专业的强烈反对体。
因此，教育部长，技术大学和在经济衰退的国家专业协会所考虑的一系列的关键问题是：•为什么继续以同样的速度生产民用工程师，鉴于公共和私人投资基础设施将在接下来的15年里大幅减少？•如何保持新增土木工程师的就业岗位？•如何将大多数人不会有机会在毕业后获得一段时间的实践经验，从而达到理论知识的更新？•如何在二十一世纪更好的解决土木工程师的需求？在本文中，提出了一种激进改革的CES国家在经济衰退。
下面的评论现有的文献，包括ASCE体为第二十一世纪，IPMA的能力的基础知识，它提出了拓宽CES课程在历史的和被广泛接受的5年任期。
在这个方向，其中，建议提高毕业生的职业潜力和就业能力：•显著增加所提供的模块，项目管理；•在CES上添加新的模块的战略管理，领导行为，交货期管理，组织和环境等；2文献综述在当时现代观教育行业从业人员中正在挑战21世纪建筑业需要新的思维和工程教育的方法。
事实上，该一个行业的可持续性是依赖于它的学习和适应能力具有变化的世界(Chan et al. 2002).众多研究一致同意大多数的学术计划未能有效地解决在经营管理以及建筑行业专业人士的需求，需要在许多地区的学生做好充分的准备适应增加的土木工程课程，使他们能够应对挑战当今商业环境的变化。
事实上，建筑业的增长的复杂性需要更加重视建设项目管理课程，从而使学生咋更广泛的基础知识在管理和经济领域上有着必要性。
此外，培养技能相关领导，沟通，谈判，解决问题，团队精神和批判性思维是必要的(Yepes et al. 2012, Cheah et al.2005,Teixeira et al. 2006, Riley 2008, Edum-Fotwe and McCaffer 2000)。
Chinowski（2002）表明，这一改革是必要的，以防止土木工程专业在大学中的所占比重进一步的下降，并且明确行业未来毕业生对工程业务有更大的欲望。
Toor and Ofori (2008)指出，未来的建筑专业人员的培训不是学术界的专有责任,它各需要各个大学、行业和专业团体积极参与贡献。
Cheah et al. (2005)在从东南亚学士学位计划的经验的报告显示，目前对土木工程范围已经增加到涵盖了广泛的专业领域的趋势（如结构，岩土工程，交通运输工程），导致工程师关于各个领域都有所了解却缺乏足够的相关单一专业领域的知识。
在这种情况下，他们更倾向于一个更一般的土木工程的形成度结来合更多的相关专业学科研究生/硕士水平的专业人士。
Christodoulou (2004)重新设计了加应力的学术课程，有利于从学科如信息技术和数据库管理系统的材料需求。
此外，阿迪蒂和住宿（2010）凸显表示经常忽略了像合同管理的主体的重要性，建筑设备管理和项目调度。
此外，对于欧洲的土木工程主题网络教育和培训(EUCEET)已经开始彻底的调查，在欧洲对于当代相关的问题的挑战，土木工程教育和职业已使公民的改革建议工程的核心课程（2001，2006）。
Sinha et al. (2007)另外提到在土木工程课程框架下道德决策的需求和挑战整的整合，而Russell et al. (2007)注意到提供学生有机会用项目作为一种教育载体与专业人员进行互动的重要性。
重要的基于项目课程对行业要求的实现也强调了米尔斯和（2003）。
在同一理论上，Chan et al. (2002)强调学生应该有机会通过互访和考察国外来参与高级专业人士以及获得国际和多元文化所涉及的指导方案。
Xanthopoulos（2012）还增加了一个有效的课程不仅包括一个广泛、一致和强大的科学背景，还保证了培养独立获取知识的方法和技巧。
Bernold (2005)也强调势在必行需要在工程教学方法根本性的改变，使学生积极参与学习过程。
根据上述意见，ASCE政策声明支持通过465个需要重建专业实践的理论基础的介绍（2008）和主体的知识（BOK）组成的24个结果（4个基础，11个技术，9个专业）。
这些必要的知识的深度和广度的描述，要求未来的土木工程师需要为了进入专业实践技能和态度进行充分的准备。
这些结果将在ASCE推荐的成果完成的底线（知识，理解，应用，分析，综合，评价）相结合的教育（本科以及硕士）的进步，结构化的工程经验。
Russell (2013)指出，ASCE的BOK已被证明是一个影响对话和工程人才培养的变化的有效的框架。
Schexnayder and Anderson (2011)指出ASCE和BOK意识到本科学位相应的专业执照和土木工程实践过程中是严重不足的，承认在专业等级和将实践行业转移到知识的现实，而后者需要更高程度的认知能力可以通过在工程教育更多的深度和广度得到。
类似的建议还包括美国国家工程院土木工程实践研究的未来教育（2004，2005）。
ICB-IPMA (2006)也认识到在三大范围（技术，行为和联系）的一个相似的相关能力的分类系列为当下的项目经理所必要的能力。
技术能力指示的项目要求和目标，项目团队，知识组织，成本财务，采购和合同。
必要的行为能力的人当中包括领导，动机，开放，创新与伦理。
联系的能力是相关的项目中的其他人，计划和投资组合的定位与实施，业务，人员管理，健康，安全，环境和安全。
对于有助于项目经理的能力的机制，通过Edum-Fotwe和McCaffer(2000)的调查，在英国170个参与实践的项目经理，表明学术课程等级低于在职正式的行业培训，这是由工作实际经验的贡献排名的。
针对希腊的土木工程专业，这多年来一直被视为一个稳定和高价值的职业生涯的决定(Latinopoulos 2010)并且一直吸引高层次的学生。
然而，建设行业是受当前的经济危机影响最严重行业，而土木工程师的失业率，尤其是年轻人，是有史以来最高的。
持续减少的建设部门在过去的四年中已经导致减少了185000工作。
ambropoulos(2003, 2004)向专业化创作在土木工程学院建设管理层作了具体的低成本和短期建议，希腊雅典国立科技大学（NTUA）注意，重整希腊现代土木工程师的轮廓的迫切需要。
Papayannakis et al.(2008) 和Karlaftis(2013)突出表示用于培养的需要创业和管理在希腊在工程课程的技能。
3提出的改革3.1推理改革方案必须为实施，从一种长远来看，也更方便支持和实施。
为了通过并实施，在有关国家和时间上它不应该破坏而应该是广泛接受的原则和大众的想法。
在土木工程研究改革放在具体方案因素的框架中。
研究改革将在国家级行业和经济的影响，尤其是它将改变学生和教授日常生活和学习视野的两个主要因素。
几十年来，学生在选择土木工程由于其职业在社会中加上所提供的工作满意的报酬和很高的地位。
因此，在大学入学考试中很多学生选择土木工程专业的学校。
在最近土木工程中的失业率的增长已经改变了学生们的视角，必须扭转为了避免长期影响行业。
土木工程教授通常是前高等级学生的个人倾向的理论问题研究。
他们随后的深入的专业化繁琐的路线和重复性评价资深同事。
在他们的多数人，他们拥有有限的经验（相对于他们的专业化）和缺乏施工经验和项目实施全球和相结合方法。
最近的金融危机对学生和他们的教授来讲都非常的困难。
学生的家庭预算大大减少，都在国内外的研究生的研究都变得有限此外，因为在很多国家，平均学生毕业通常是六年而不是五年，他们的家庭经济压力大，这将被改善。
对上述来说，教授们面临大幅降低工资，严重影响了他们的道德。
此外，退休的教授都是在非常低的速度取代，即活动的教授的总数量切实减少。