土木工程英文论文翻译
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。
土木工程专业英语(带翻译)
State-of-the-art report of bridge health monitoring AbstractThe damage diagnosis and healthmonitoring of bridge structures are active areas of research in recent years. Comparing with the aerospace engineering and mechanical engineering, civil engineering has the specialities of its own in practice. For example, because bridges, as well as most civil engineering structures, are large in size, and have quite lownatural frequencies and vibration levels, at low amplitudes, the dynamic responses of bridge structure are substantially affected by the nonstructural components, unforeseen environmental conditions, and changes in these components can easily to be confused with structural damage.All these give the damage assessment of complex structures such as bridges a still challenging task for bridge engineers. This paper firstly presents the definition of structural healthmonitoring system and its components. Then, the focus of the discussion is placed on the following sections:①the laboratory and field testing research on the damage assessment;②analytical developments of damage detectionmethods, including (a) signature analysis and pattern recognition approaches, (b) model updating and system identification approaches, (c) neural networks approaches; and③sensors and their optimum placements. The predominance and shortcomings of each method are compared and analyzed. Recent examples of implementation of structural health monitoring and damage identification are summarized in this paper. The key problem of bridge healthmonitoring is damage automatic detection and diagnosis, and it is the most difficult problem. Lastly, research and development needs are addressed.1 IntroductionDue to a wide variety of unforeseen conditions and circumstance, it will never be possible or practical to design and build a structure that has a zero percent probability of failure. Structural aging, environmental conditions, and reuse are examples of circumstances that could affect the reliability and thelife of a structure. There are needs of periodic inspections to detect deterioration resulting from normal operation and environmental attack or inspections following extreme events, such as strong-motion earthquakes or hurricanes. To quantify these system performance measures requires some means to monitor and evaluate the integrity of civil structureswhile in service. Since the Aloha Boeing 737 accident that occurred on April 28, 1988, such interest has fostered research in the areas of structural health monitoring and non-destructive damage detection in recent years.According to Housner, et al. (1997), structural healthmonitoring is defined as“the use ofin-situ,non-destructive sensing and analysis of structural characteristics, including the structural response, for detecting changes that may indicate damage or degradation”[1]. This definition also identifies the weakness. While researchers have attempted the integration of NDEwith healthmonitoring, the focus has been on data collection, not evaluation. What is needed is an efficient method to collect data from a structure in-service and process the data to evaluate key performance measures, such as serviceability, reliability, and durability. So, the definition byHousner, et al.(1997)should be modified and the structural health monitoring may be defined as“the use ofin-situ,nondestructive sensing and analysis of structural characteristics, including the structural response, for the purpose of identifying if damage has occurred, determining the location of damage, estimatingthe severityof damage and evaluatingthe consequences of damage on the structures”(Fig.1). In general, a structural health monitoring system has the potential to provide both damage detection and condition assessment of a structure.Assessing the structural conditionwithout removingthe individual structural components is known as nondestructive evaluation (NDE) or nondestructive inspection. NDE techniques include those involving acoustics, dye penetrating,eddy current, emission spectroscopy, fiber-optic sensors, fiber-scope, hardness testing, isotope, leak testing, optics, magnetic particles, magnetic perturbation, X-ray, noise measurements, pattern recognition, pulse-echo, ra-diography, and visual inspection, etc. Mostof thesetechniques have been used successfullyto detect location of certain elements, cracks orweld defects, corrosion/erosion, and so on. The FederalHighwayAdministration(FHWA, USA)was sponsoring a large program of research and development in new technologies for the nondestructive evaluation of highway bridges. One of the two main objectives of the program is to develop newtools and techniques to solve specific problems. The other is to develop technologies for the quantitative assessment of the condition of bridges in support of bridge management and to investigate howbest to incorporate quantitative condition information into bridge management systems. They hoped to develop technologies to quickly, efficiently, and quantitatively measure global bridge parameters, such as flexibility and load-carrying capacity. Obviously, a combination of several NDE techniques may be used to help assess the condition of the system. They are very important to obtain the data-base for the bridge evaluation.But it is beyond the scope of this review report to get into details of local NDE.Health monitoring techniques may be classified as global and local. Global attempts to simultaneously assess the condition of the whole structure whereas local methods focus NDE tools on specific structural components. Clearly, two approaches are complementaryto eachother. All such available informationmaybe combined and analyzed by experts to assess the damage or safety state of the structure.Structural health monitoring research can be categorized into the following four levels: (I) detecting the existence of damage, (II) findingthe location of damage, (III) estimatingthe extentof damage, and (IV) predictingthe remaining fatigue life. The performance of tasks of Level (III) requires refined structural models and analyses, local physical examination, and/or traditional NDE techniques. To performtasks ofLevel (IV) requires material constitutive information on a local level, materials aging studies, damage mechanics, and high-performance computing. With improved instrumentation and understanding of dynamics of complex structures, health monitoring and damage assessment of civil engineering structures has become more practical in systematic inspection andevaluation of these structures during the past two decades.Most structural health monitoringmethods under current investigation focus on using dynamic responses to detect and locate damage because they are global methods that can provide rapid inspection of large structural systems.These dynamics-based methods can be divided into fourgroups:①spatial-domain methods,②modal-domain methods,③time-domain methods, and④frequency- domain methods. Spatial-domain methods use changes of mass, damping, and stiffness matrices to detect and locate damage. Modal-domain methods use changes of natural frequencies, modal damping ratios, andmode shapesto detect damage. In the frequency domain method, modal quantities such as natural frequencies, damping ratio, and model shapes are identified.The reverse dynamic systemof spectral analysis and the generalized frequency response function estimated fromthe nonlinear auto-regressive moving average (NARMA) model were applied in nonlinear system identification. In time domainmethod, systemparameterswere determined fromthe observational data sampled in time. It is necessaryto identifythe time variation of systemdynamic characteristics fromtime domain approach if the properties of structural system changewith time under the external loading condition. Moreover, one can use model-independent methods or model-referenced methods to perform damage detection using dynamic responses presented in any of the four domains. Literature shows that model independent methods can detect the existence of damage without much computational efforts, butthey are not accurate in locating damage. On the otherhand, model-referencedmethods are generally more accurate in locating damage and require fewer sensors than model-independent techniques, but they require appropriate structural models and significant computational efforts. Although time-domain methods use original time-domain datameasured using conventional vibrationmeasurement equipment, theyrequire certain structural information and massive computation and are case sensitive. Furthermore, frequency- and modal-domain methods use transformed data,which contain errors and noise due totransformation.Moreover, themodeling and updatingofmass and stiffnessmatrices in spatial-domain methods are problematic and difficult to be accurate. There are strong developmenttrends that two or three methods are combined together to detect and assess structural damages.For example, several researchers combined data of static and modal tests to assess damages. The combination could remove the weakness of each method and check each other. It suits the complexity of damage detection.Structural health monitoring is also an active area of research in aerospace engineering, but there are significant differences among the aerospace engineering, mechanical engineering, and civil engineering in practice. For example,because bridges, as well as most civil engineering structures, are large in size, and have quite lownatural frequencies and vibration levels, at lowamplitudes, the dynamic responses of bridge structure are substantially affected by the non-structural components, and changes in these components can easily to be confused with structural damage. Moreover,the level of modeling uncertainties in reinforced concrete bridges can be much greater than the single beam or a space truss. All these give the damage assessment of complex structures such as bridges a still challenging task for bridge engineers. Recent examples of research and implementation of structural health monitoring and damage assessment are summarized in the following sections.2 Laboratory and field testing researchIn general, there are two kinds of bridge testing methods, static testing and dynamic testing. The dynamic testing includes ambient vibration testing and forced vibration testing. In ambient vibration testing, the input excitation is not under the control. The loading could be either micro-tremors, wind, waves, vehicle or pedestrian traffic or any other service loading. The increasing popularity of this method is probably due to the convenience of measuring the vibrationresponse while the bridge is under in-service and also due to the increasing availability of robust data acquisition and storage systems. Since the input is unknown, certain assumptions have to be made. Forced vibration testing involves application of input excitation of known force level at known frequencies. The excitation manners include electro-hydraulic vibrators, forcehammers, vehicle impact, etc. The static testing in the laboratory may be conducted by actuators, and by standard vehicles in the field-testing.we can distinguish that①the models in the laboratory are mainly beams, columns, truss and/or frame structures, and the location and severity of damage in the models are determined in advance;②the testing has demonstrated lots of performances of damage structures;③the field-testing and damage assessmentof real bridges are more complicated than the models in the laboratory;④the correlation between the damage indicator and damage type,location, and extentwill still be improved.3 Analytical developmentThe bridge damage diagnosis and health monitoring are both concerned with two fundamental criteria of the bridges, namely, the physical condition and the structural function. In terms of mechanics or dynamics, these fundamental criteria can be treated as mathematical models, such as response models, modal models and physical models.Instead of taking measurements directly to assess bridge condition, the bridge damage diagnosis and monitoring systemevaluate these conditions indirectly by using mathematical models. The damage diagnosis and health monitoring are active areas of research in recentyears. For example, numerous papers on these topics appear in the proceedings of Inter-national Modal Analysis Conferences (IMAC) each year, in the proceedings of International Workshop on Structural HealthMonitoring (once of two year, at Standford University), in the proceedings of European Conference on Smart materials and Structures and European Conference on Structural Damage AssessmentUsing Advanced Signal Processing Procedures, in the proceedings ofWorld Conferences of Earthquake Engineering, and in the proceedings of International Workshop on Structural Control, etc.. There are several review papers to be referenced, for examples,Housner, et al. (1997)provided an extensive summary of the state of the art in control and health monitoring of civil engineering structures[1].Salawu (1997)discussed and reviewed the use of natural frequency as a diagnostic parameter in structural assessment procedures using vibrationmonitoring.Doebling, Farrar, et al. (1998)presented a through review of the damage detection methods by examining changes in dynamic properties.Zou, TongandSteven (2000)summarized the methods of vibration-based damage and health monitoring for composite structures, especially in delamination modeling techniques and delamination detection.4 Sensors and optimum placementOne of the problems facing structural health monitoring is that very little is known about the actual stress and strains in a structure under external excitations. For example, the standard earthquake recordings are made ofmotions of the floors of the structure and no recordings are made of the actual stresses and strains in structural members. There is a need for special sensors to determine the actual performance of structural members. Structural health monitoring requires integrated sensor functionality to measure changes in external environmental conditions, signal processing functionality to acquire, process, and combine multi-sensor and multi-measured information. Individual sensors and instrumented sensor systems are then required to provide such multiplexed information.FuandMoosa (2000)proposed probabilistic advancing cross-diagnosis method to diagnosis-decision making for structural health monitoring. It was experimented in the laboratory respectively using a coherent laser radar system and a CCD high-resolution camera. Results showed that this method was promising for field application. Another new idea is thatneural networktechniques are used to place sensors. For example,WordenandBurrows (2001)used the neural network and methods of combinatorial optimization to locate and classify faults.The static and dynamic data are collected from all kinds of sensorswhich are installed on the measured structures.And these datawill be processed and usable informationwill be extracted. So the sensitivity, accuracy, and locations,etc. of sensors are very important for the damage detections. The more information are obtained, the damage identification will be conducted more easily, but the price should be considered. That’s why the sensors are determinedin an optimal ornearoptimal distribution. In aword, the theory and validation ofoptimumsensor locationswill still being developed.5 Examples of health monitoring implementationIn order for the technology to advance sufficiently to become an operational system for the maintenance and safety of civil structures, it is of paramount importance that new analytical developments are ultimately verified with appropriate data obtained frommonitoring systems, which have been implemented on civil structures, such as bridges.Mufti (2001)summarized the applications of SHM of Canadian bridge engineering, including fibre-reinforced polymers sensors, remote monitoring, intelligent processing, practical applications in bridge engineering, and technology utilization. Further study and applications are still being conducted now.FujinoandAbe(2001)introduced the research and development of SHMsystems at the Bridge and Structural Lab of the University of Tokyo. They also presented the ambient vibration based approaches forLaser DopplerVibrometer (LDV) and the applications in the long-span suspension bridges.The extraction of the measured data is very hard work because it is hard to separate changes in vibration signature duo to damage form changes, normal usage, changes in boundary conditions, or the release of the connection joints.Newbridges offer opportunities for developing complete structural health monitoring systems for bridge inspection and condition evaluation from“cradle to grave”of the bridges. Existing bridges provide challenges for applying state-of-the-art in structural health monitoring technologies to determine the current conditions of the structural element,connections and systems, to formulate model for estimating the rate of degradation, and to predict the existing and the future capacities of the structural components and systems. Advanced health monitoring systems may lead to better understanding of structural behavior and significant improvements of design, as well as the reduction of the structural inspection requirements. Great benefits due to the introduction of SHM are being accepted by owners, managers, bridge engineers,etc..6 Research and development needsMost damage detection theories and practices are formulated based on the following assumption: that failure or deterioration would primarily affect the stiffness and therefore affect the modal characteristics of the dynamic response of the structure. This is seldom true in practice, because①Traditional modal parameters (natural frequency, damping ratio and mode shapes, etc.) are not sensitive enough to identify and locate damage. The estimation methods usually assume that structures are linear and proportional damping systems.②Most currently used damage indices depend on the severity of the damage, which is impractical in the field. Most civil engineering structures, such as highway bridges, have redundancy in design and large in size with low natural frequencies. Any damage index should consider these factors.③Scaledmodelingtechniques are used in currentbridge damage detection. Asingle beam/girder models cannot simulate the true behavior of a real bridge. Similitude laws for dynamic simulation and testing should be considered.④Manymethods usually use the undamaged structural modal parameters as the baseline comparedwith the damaged information. This will result in the need of a large data storage capacity for complex structures. But in practice,there are majority of existing structures for which baseline modal responses are not available. Only one developed method(StubbsandKim (1996)), which tried to quantify damagewithout using a baseline, may be a solution to this difficulty. There is a lot of researchwork to do in this direction.⑤Seldommethods have the ability to distinguish the type of damages on bridge structures. To establish the direct relationship between the various damage patterns and the changes of vibrational signatures is not a simple work.Health monitoring requires clearly defined performance criteria, a set of corresponding condition indicators and global and local damage and deterioration indices, which should help diagnose reasons for changes in condition indicators. It is implausible to expect that damage can be reliably detected or tracked byusing a single damage index. We note that many additional localized damage indiceswhich relate to highly localized properties ofmaterials or the circumstances may indicate a susceptibility of deterioration such as the presence of corrosive environments around reinforcing steel in concrete, should be also integrated into the health monitoring systems.There is now a considerable research and development effort in academia, industry, and management department regarding global healthmonitoring for civil engineering structures. Several commercial structural monitoring systems currently exist, but further development is needed in commercialization of the technology. We must realize that damage detection and health monitoring for bridge structures by means of vibration signature analysis is a very difficult task. Itcontains several necessary steps, including defining indicators on variations of structural physical condition, dynamic testing to extract such indication parameters, defining the type of damages and remaining capacity or life of the structure, relating the parameters to the defined damage/aging. Unfortunately, to date, no one has accomplished the above steps. There is a lot of work to do in future.桥梁健康监测应用与研究现状摘要桥梁损伤诊断与健康监测是近年来国际上的研究热点,在实践方面,土木工程和航空航天工程、机械工程有明显的差别,比如桥梁结构以及其他大多数土木结构,尺寸大、质量重,具有较低的自然频率和振动水平,桥梁结构的动力响应极容易受到不可预见的环境状态、非结构构件等的影响,这些变化往往被误解为结构的损伤,这使得桥梁这类复杂结构的损伤评估具有极大的挑战性.本文首先给出了结构健康监测系统的定义和基本构成,然后集中回顾和分析了如下几个方面的问题:①损伤评估的室内实验和现场测试;②损伤检测方法的发展,包括:(a)动力指纹分析和模式识别方法, (b)模型修正和系统识别方法, (c)神经网络方法;③传感器及其优化布置等,并比较和分析了各自方法的优点和不足.文中还总结了健康监测和损伤识别在桥梁工程中的应用,指出桥梁健康监测的关键问题在于损伤的自动检测和诊断,这也是困难的问题;最后展望了桥梁健康监测系统的研究和发展方向.关键词:健康监测系统;损伤检测;状态评估;模型修正;系统识别;传感器优化布置;神经网络方法;桥梁结构1概述由于不可预见的各种条件和情况下，设计和建造一个结构将永远不可能或无实践操作性，它有一个失败的概率百分之零。
土木工程英文文献及翻译-英语论文.doc
土木工程英文文献及翻译-英语论文土木工程英文文献及翻译in Nanjing, ChinaZhou Jin, Wu Yezheng *, Yan GangDepartment of Refrigeration and Cryogenic Engineering, School of Energy and Power Engineering, Xi’an Jiao Tong University,Xi’an , PR ChinaReceived 4 April 2005; accepted 2 October 2005Available online 1 December 2005AbstractThe bin method, as one of the well known and simple steady state methods used to predict heating and cooling energyconsumption of buildings, requires reliable and detailed bin data. Since the long term hourly temperature records are notavailable in China, there is a lack of bin weather data for study and use. In order to keep the bin method practical in China,a stochastic model using only the daily maximum and minimum temperatures to generate bin weather data was establishedand tested by applying one year of measured hourly ambient temperature data in Nanjing, China. By comparison with themeasured values, the bin weather data generated by the model shows adequate accuracy. This stochastic model can be usedto estimate the bin weather data in areas, especially in China, where the long term hourly temperature records are missingor not available.Ó 2005 Elsevier Ltd. All rights reserved.Keywords: Energy analysis; Stochastic method; Bin data; China1. IntroductionIn the sense of minimizing the life cycle cost of a building, energy analysis plays an important role in devel-oping an optimum and cost effective design of a heating or an air conditioning system for a building. Severalmodels are available for estimating energy use in buildings. These models range from simple steady state mod-els to comprehensive dynamic simulation procedures.Today, several computer programs, in which the influence of many parameters that are mainly functionsof time are taken into consideration, are available for simulating both buildings and systems and performinghour by hour energy calculations using hourly weather data. DOE-2, BLAST and TRNSYS are such* Corresponding author. Tel.: +86 29 8266 8738; fax: +86 29 8266 8725.E-mail address: yzwu@ (W. Yezheng).0196-8904/$ - see front matter Ó 2005 Elsevier Ltd. All rights reserved.doi:10.1016/NomenclatureZ. Jin et al. / Energy Conversion and Management 47 (2006) 1843–1850number of daysfrequency of normalized hourly ambient temperatureMAPE mean absolute percentage error (%)number of subintervals into which the interval [0, 1] was equally dividednumber of normalized temperatures that fall in subintervalprobability densityhourly ambient temperature (°C)normalized hourly ambient temperature (dimensionless)weighting factorSubscriptscalculated valuemeasured valuemax daily maximummin daily minimumprograms that have gained widespread acceptance as reliable estimation tools. Unfortunately, along withthe increased sophistication of these models, they have also become very complex and tedious touse [1].The steady state methods, which are also called single measure methods, require less data and provideadequate results for simple systems and applications. These methods are appropriate if the utilization ofthe building can be considered constant. Among these methods are the degree day and bin data methods.The degree-day methods are the best known and the simplest methods among the steady state models.Traditionally, the degree-day method is based on the assumption that on a long term average, the solarand internal gains will offset the heat loss when the mean daily outdoor temperature is 18.3 °C and thatthe energy consumption will be proportional to the difference between 18.3 °C and the mean daily tempera-ture. The degree-day method can estimate energy consumption very accurately if the building use and theefficiency of the HVAC equipment are sufficiently constant. However, for many applications, at least oneof the above parameters varies with time. For instance, the efficiency of a heat pump system and HVAC equip-ment may be affected directly or indirectly by outdoor temperature. In such cases, the bin method can yieldgood results for the annual energy consumption if different temperature intervals and time periods areevaluated separately. In the bin method, the energy consumption is calculated for several values of the outdoortemperature and multiplied by the number of hours in the temperature interval (bin) centered around thattemperature. Bin data is defined as the number of hours that the ambient temperature was in each of a setof equally sized intervals of ambient temperature.In the United States, the necessary bin weather data are available in the literature [2,3]. Some researchers[4–8] have developed bin weather data for other regions of the world. However, there is a lack of informationin the ASHRAE handbooks concerning the bin weather data required to perform energy calculations in build-ings in China. The practice of analysis of weather data for the design of HVAC systems and energy consump-tion predictions in China is quite new. For a long time, only the daily value of meteorological elements, such asdaily maximum, minimum and average temperature, was recorded and available in most meteorologicalobservations in China, but what was needed to obtain the bin weather data, such as temperature bin data,were the long term hourly values of air temperature. The study of bin weather data is very limited in China.Only a few attempts [9,10] in which bin weather data for several cities was given have been found in China.Obviously, this cannot meet the need for actual use and research. So, there is an urgent need for developing binweather data in China. The objective of this paper, therefore, is to study the hourly measured air temperaturedistribution and then to establish a model to generate bin weather data for the long term daily temperaturedata.2. Data usedZ. Jin et al. / Energy Conversion and Management 47 (2006) 1843–1850In this paper, to study the hourly ambient temperature variation and to establish and evaluate the model, aone year long hourly ambient temperature record for Nanjing in 2002 was used in the study. These data aretaken from the Climatological Center of Lukou Airport in Nanjing, which is located in the southeast of China(latitude 32.0°N, longitude 118.8°E, altitude 9 m).In addition, in order to create the bin weather data for Nanjing, typical weather year data was needed.Based on the long term meteorological data from 1961 to 1989 obtained from the China MeteorologicalAdministration, the typical weather year data for most cities in China has been studied in our former research[11] by means of the TMY (Typical Meteorological Year) method. The typical weather year for Nanjing isshown in Table 1. As only daily values of the meteorological elements were recorded and available in China,the data contained in the typical weather year data was also only daily values. In this study, the daily maxi-mum and minimum ambient temperature in the typical weather year data for Nanjing was used.3. Stochastic model to generate bin dataTraditionally, the generation of bin weather data needs long term hourly ambient temperature records.However, in the generation, the time information, namely the exact time that such a temperature occurredin a day, was omitted, and only the numerical value of the temperature was used. So, the value of each hourlyambient temperature can be treated as the independent random variable, and its distribution within the dailytemperature range can be analyzed by means of probability theory.3.1. Probability distribution of normalized hourly ambient temperatureSince the daily maximum and minimum temperatures and temperature range varied day by day, the con-cept of normalized hourly ambient temperature should be introduced to transform the hourly temperatures ineach day into a uniform scale. The new variable, normalized hourly ambient temperature is defined by^ ¼ttmintmaxtminwhere ^ may be termed the normalized hourly ambient temperature, tmaxand tminare the daily maximum andminimum temperatures, respectively, t is the hourly ambient temperature. Obviously, the normalized hourly ambient temperature ^ is a random variable that lies in the interval [0, 1].To analyze its distribution, the interval [0, 1] can be divided equally into several subintervals, and by means ofthe histogram method [12]iin each subinterval can be calculated by1137土木工程英文文献及翻译Based on the one year long hourly ambient temperature data in Nanjing, China, the probability density piwas calculated for the whole day and the 08:00–20:00 period, where the interval [0, 1] was equally divided into50 subintervals, namely n equals 50. The results are shown in Fig. 1.According to the discrete probability density data in Fig. 1, the probability density function of ^ can beobtained by a fitting method. In this study, the quadratic polynomialswere used to fit the probability density data, where a, b and c are coefficients. According to the property of theprobability density function, the following equation should be satisfiedAs shown in Fig. 1, the probability density curve obtained according to the probability density data pointsis also shown. The probability densit y functions that are fitted are described byp ¼ 2:7893^23:1228^ þ 1:6316 for the whole day periodp ¼ 2:2173^20:1827^ þ 0:3522 for the 08 : 00–20 : 00 period3.2. The generation of hourly ambient temperatureAs stated in the beginning of this paper, the objective of this study is to generate the hourly ambient tem-perature needed for bin weather data generation in the case that only the daily maximum and minimum tem-peratures are known. To do this, we can use the obtained probability density function to generate thenormalized hourly ambient temperature and then transform it to hourly temperature. This belongs to theproblem of how to simulate a random variable with a prescribed probability density function and can be doneon a computer by the method described in the literature [13]. For a given probability density function f ð^Þ, ifits distribution function F ð^Þ can be obtained and if u is a random variable with uniform distribution on [0, 1],thenF, we need only setAs stated above, the probability density function of the normalized ambient temperature was fitted using aone year long hourly temperature data. Based on the probability density function obtained, the random nor-malized hourly temperature can be generated. When the daily maximum and minimum temperature areknown, the normalized hourly temperature can be transformed to an actual temperature by the followingequationWhen the hourly temperature for a particular period of the day has been generated using the above method,the bin data can also be obtained. Because the normalized temperature generated using the model in this studyis a random variable, the bin data obtained from each generation shows somedifference, but it has much sim-ilarity. To obtain a stable result of bin data, the generation of the bin data can be performed enough times,and the bin data can be obtained by averaging the result of each generation. In this paper, 50 generations wereaveraged to generate the bin weather data.Z. Jin et al. / Energy Conversion and Management 47 (2006) 1843–18503.4. Methods of model evaluationThe performance of the model was evaluated in terms of the following statistical error test:土木工程英文文献及翻译一种产生bin气象数据的随机方法——中国南京周晋摘要：bin方法是一种众所周知且简捷的稳态的计算方法，可以用来预计建筑的冷热能耗。
土木工程毕业设计英文翻译论文
Structural FormsStructural forms, such as the beam or the arch ,have developed through the ages in relation to the availability of materials and the technology of the time. The arch, for instance, undoubtedly developed as a result of the availability of brick. In the technology of buildings .every structure must work against gravity ,which tends to pull everything down to the ground .A balance must therefore be attained between the force of gravity ,the shape of the structure ,and the strength of the material used. To provide a cover over a sheltered space and permit openings in the walls that surround it ,builders have developed four techniques are post and lintel, arch and vault, truss, and cantilever construction.Post and lintel. In post and lintel construction ,a horizontal beam is placed across the space between two supporting posts. If the support is continuous, it is called a wall; if a series of beams are joined together into a continuous surface, it is called a slab.Simple rectilinear buildings result from post and lintel construction, which is characteristic of much primitive construction as well as of the classical Greek temples. In this type of construction, the post (or column) carries only a vertical weight, or load, and is therefore under compression, and the lintel (or beam) is bent by the loads acting transversely to its axis. Therefore , the post must have compressive strength, and the beam must have bending strength. Both wood and stone were used in early example of this type of construction , although the limited bending strength of stone dictated the close column spacing which is apparent in Greek temples. For example, in the Parthenon in Athens, the space between the columns is approximately equal to the column diameter.Modern building materials such as steel and reinforced concrete are used to advantage in post and lintel construction. The skeleton frame of a modern steel skyscraper, for instance, consists of beams and columns in a three-dimensional post and lintel network, or grid. The typical wood fame house, with closely spaced wooden post, or studs, and floors with a series of closely spaced wood beams, or joists, also illustrates post and lintel construction.Just as a house of cards can support vertical loads but collapses under a slightbreath of air, the post and lintel system can topple under winds or earthquakes, but of which impose a horizontal force. This collapse is due to the fact that the joint between the column and beam acts as if it were a hinge .In earlier times this lateral instability was not apparent because the weight and the mass of the materials (particularly stone) and the limited height of the structures negated the importance of horizontal forces. In tall modern building that have slender elements made of strong and light materials such as steel, lateral instability becomes a significant factor . To provide the necessary lateral resistance, a rigid connection must be made between the vertical column and horizontal beam. This creates a rigid frame; it is used to achieve lateral stability in skyscraper construction.Arch. The arch which is characteristically a masonry type of construction, undoubtedly had its origin in Mesopotamia，a land of brick buildings. Arches consist of masonry blocks in the form of a curved line. In principle, each wedge-shaped masonry block cannot fall inward without pushing the others out ;thus, the whole arch form remains stable as long as a force is applied at the base to keep it from spreading. This force is called a horizontal thrust. A continuous series of arches is known as a vault.The Etruscans, by their examples of arch constructions in bridges and gates, probably inspired the Roman to experiment with this type of construction about 600 B.C. However, it was not until the last years of the Roman republic that tunnel vaults and intersecting, or groined, vaults were used to cover large rooms. The form of the Roman arch or vault is generally semicircular for reasons of geometric simplicity. As a result, all wedge-shaped stones are identical; their curved edges are equidistant from the center of the circle ,and their straight edges lie on equally spaced lines radiating from the center. This type of semicircular arch was widely used by the Romans in buildings such as the Basilica of Constantine and the Baths of Caracalla and in gates such as the Porta Maggiore in Rome.The Gothic arch, which is characterized by its pointed shape ,evolved in France in the 12th century. This form characterizes some of the most magnificent churches of the early Renaissance period such as the Chartres. Amiens, and Rheims cathedral. theform of the Gothic arch is superior to the Roman arch because of its greater structural clarity, which closely approaches the shapes the shape of an idea arch. The concept of the idea arch can best be explained by a comparison with a suspension cable.A chain or a cable supported at each end assumes a curved shape called a catenary (from catena, chain).If the cable were required to support one weight hung from it ,it would change shape to adjust to this condition ;this is due to the fact that a cable carries loads only by the actin of simple tension along the length of the cable. If, instead of a single load, many parabola. The catenary and the parabola are geomertrically similar since the weight of the cable is approximately a uniformly distributed load .An ideal arch may be thought of as a cable frozen in its shape and turned upside down.(Instead of carrying loads by tension, as in the cable, the ideal arch carries loads by simple compression)This ideal shape of load the arch is called the “funicular curve” A different funicular curve exists for every type of load the arch is required to carry. Since the arch ,unlike the flexible cable ,cannot adjust its shape to the load ,then the arch, under a load other than that which gave it its funicular shape, must also carry the load by bending, as in a beam .The structural efficiency of an arch can thus be measured in terms of the proximity of the geometric shape to the funicular curve ,In the semicircular Romans arch ,there is a large difference between the funicular curve of the loads and the circular shape. The pointed Gothic arches are much closer to the funicular curve of the loads and therefore possess a clear advantage over the earlier semicircular form.To resist the horizontal thrust which exists at the base of an arch ,the Roman used massive piers or buttresses. In some of the Gothic cathedrals, which raised the arch high above the nave, flying buttresses over the side aisles were used to counteract the thrust.In modern times ,arch construction has been used extensively for bridge, utilizing steel, wood, or reinforced concrete. The concrete arch bridges built by Robert Maillart in Switzerland are outstanding examples of elegance and structural clarity in modern arch design.Truss. The simplest form of truss is a triangle consisting of three bars. Thiselementary truss form undoubtedly grew out of the use of the gabled roof for small houses and churches. In this construction, two slanting rafters rest on top of a wall and are pinned at the peak. The load of the roof tends to push out the top of the walls. Tying the bottom of the rafters together with a bar or rod counters this outward push. The resulting triangular shape is a rigid form geometrically, because none of its angles can change without changing the length of its sides. Each element in a truss is subject to either tension or compression; in the simple triangular truss, the rafters are in compression and the tie rod is in tension.The elementary triangular truss is limited to spanning relatively short distance because each slanting member is long compared to the span. In a triangular truss with equal angles, for instance, each member is as long as the span. This drawback was recognized by Andrea Palladio in the 16th century. His design for a trussed bridge utilized the principle that if a single triangles is rigid ,combinations of triangles are also rigid . By arranging short lengths of timbers in a series of triangles to form complex trusses, almost any distance can be spanned.It was not until the 19th century , when mathematical methods of analysis became known and iron and steel were introduced, that trusses with a great degree of perfection and elegance were developed. Modern trusses with a variety of configurations are used to span auditoriums, armories, and convention halls , creating large column-free spaces. The type of trusses most commonly used in buildings are the Pratt, Howe, and Warren trusses, all named after their inventors. The Pratt and Howe trusses have top and bottom chords (horizontal elements), and both verticals and diagonals between the chords. The Warren truss has only diagonals joining the top and bottom chord .Cantilever. In cantilever construction, building elements are projected outward from a fixed support. An early kind of cantilever construction was the corbel; it had its origin in the late Stone Age and can be found in the form of corbelled domes built in Sarrdinia about 2,500 B.C. In corbel construction, each successive layer of stone stands out farther from a wall in the form of upside-down steps. Only the weight of the stones above and behind the face of the wall prevent a corbel from collapsing. Anexcessive amount of material is required for corbel construction because of the necessity for heavy masonry walls.Cantilevering building elements from a wall or other fixed support permits projecting part of a building beyond the ground-level construction to gain more living area above, as in many of the Renaissance town houses.The cantilever is much used in modern buildings as a result of the availability of steel and reinforced concrete. It is a simple matter in a concrete apartment building to create a cantilevered balcony when the balcony slab is merely a continuation of the interior slab. The Kaumfman house, built by Frank Lloyd Wright in 1939, is an example of a dramatic use of cantilevers and demonstrates the potential of this type of construction. In a steel-framed building, beams can project beyond column to permit the face of the building to be a curtain wall with large glass areas. This cantilever construction was exemplified by the Bauhaus (1926) ,which was used as a model for many skyscrapers built after World WarⅡ结构形式结构形式，如梁或拱，通过发展有关的材料供应和当时的技术的年龄。
土木工程英文文献及翻译
Civil engineeringCivil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including works like bridges, roads, canals, dams, and buildings.[1][2][3] Civil engineering is the oldest engineering discipline after military engineering,[4] and it was defined to distinguish non-military engineering from military engineering.[5] It is traditionally broken into several sub-disciplines including environmental engineering, geotechnical engineering, structural engineering, transportation engineering, municipal or urban engineering, water resources engineering, materials engineering, coastal engineering,[4] surveying, and construction engineering.[6] Civil engineering takes place on all levels: in the public sector from municipal through to national governments, and in the private sector from individual homeowners through to international companies.History of the civil engineering professionSee also: History of structural engineeringEngineering has been an aspect of life since the beginnings of human existence. The earliest practices of Civil engineering may have commenced between 4000 and 2000 BC in Ancient Egypt and Mesopotamia (Ancient Iraq) when humans started to abandon a nomadic existence, thus causing a need for the construction of shelter. During this time, transportation became increasingly important leading to the development of the wheel and sailing.Until modern times there was no clear distinction between civil engineering and architecture, and the term engineer and architect were mainly geographical variations referring to the same person, often used interchangeably.[7]The construction of Pyramids in Egypt (circa 2700-2500 BC) might be considered the first instances of large structure constructions. Other ancient historic civil engineering constructions include the Parthenon by Iktinos in Ancient Greece (447-438 BC), theAppian Way by Roman engineers (c. 312 BC), the Great Wall of China by General Meng T'ien under orders from Ch'in Emperor Shih Huang Ti (c. 220 BC)[6] and the stupas constructed in ancient Sri Lanka like the Jetavanaramaya and the extensive irrigation works in Anuradhapura. The Romans developed civil structures throughout their empire, including especially aqueducts, insulae, harbours, bridges, dams and roads.In the 18th century, the term civil engineering was coined to incorporate all things civilian as opposed to military engineering.[5]The first self-proclaimed civil engineer was John Smeaton who constructed the Eddystone Lighthouse.[4][6]In 1771 Smeaton and some of his colleagues formed the Smeatonian Society of Civil Engineers, a group of leaders of the profession who met informally over dinner. Though there was evidence of some technical meetings, it was little more than a social society.In 1818 the Institution of Civil Engineers was founded in London, and in 1820 the eminent engineer Thomas Telford became its first president. The institution received a Royal Charter in 1828, formally recognising civil engineering as a profession. Its charter defined civil engineering as:the art of directing the great sources of power in nature for the use and convenience of man, as the means of production and of traffic in states, both for external and internal trade, as applied in the construction of roads, bridges, aqueducts, canals, river navigation and docks for internal intercourse and exchange, and in the construction of ports, harbours, moles, breakwaters and lighthouses, and in the art of navigation by artificial power for the purposes of commerce, and in the construction and application of machinery, and in the drainage of cities and towns.[8] The first private college to teach Civil Engineering in the United States was Norwich University founded in 1819 by Captain Alden Partridge.[9] The first degree in Civil Engineering in the United States was awarded by Rensselaer Polytechnic Institute in 1835.[10] The first such degree to be awarded to a woman was granted by Cornell University to Nora Stanton Blatchin 1905.History of civil engineeringCivil engineering is the application of physical and scientific principles, and its history is intricately linked to advances in understanding of physics and mathematics throughout history. Because civil engineering is a wide ranging profession, including several separate specialized sub-disciplines, its history is linked to knowledge of structures, materials science, geography, geology, soils, hydrology, environment, mechanics and other fields.Throughout ancient and medieval history most architectural design and construction was carried out by artisans, such as stone masons and carpenters, rising to the role of master builder. Knowledge was retained in guilds and seldom supplanted by advances. Structures, roads and infrastructure that existed were repetitive, and increases in scale were incremental.[12]One of the earliest examples of a scientific approach to physical and mathematical problems applicable to civil engineering is the work of Archimedes in the 3rd century BC, including Archimedes Principle, which underpins our understanding of buoyancy, and practical solutions such as Archimedes' screw. Brahmagupta, an Indian mathematician, used arithmetic in the 7th century AD, based on Hindu-Arabic numerals, for excavation (volume) computations.[13]Civil engineers typically possess an academic degree with a major in civil engineering. The length of study for such a degree is usually three to five years and the completed degree is usually designated as a Bachelor of Engineering, though some universities designate the degree as a Bachelor of Science. The degree generally includes units covering physics, mathematics, project management, design and specific topics in civil engineering. Initially such topics cover most, if not all, of thesub-disciplines of civil engineering. Students then choose to specialize in one or more sub-disciplines towards the end of the degree.[14]While anUndergraduate (BEng/BSc) Degree will normally provide successful students with industry accredited qualification, some universities offer postgraduate engineering awards (MEng/MSc) which allow students to further specialize in their particular area of interest within engineering.[15]In most countries, a Bachelor's degree in engineering represents the first step towards professional certification and the degree program itself is certified by a professional body. After completing a certified degree program the engineer must satisfy a range of requirements (including work experience and exam requirements) before being certified. Once certified, the engineer is designated the title of Professional Engineer (in the United States, Canada and South Africa), Chartered Engineer (in most Commonwealth countries), Chartered Professional Engineer (in Australia and New Zealand), or European Engineer (in much of the European Union). There are international engineering agreements between relevant professional bodies which are designed to allow engineers to practice across international borders.The advantages of certification vary depending upon location. For example, in the United States and Canada "only a licensed engineer may prepare, sign and seal, and submit engineering plans and drawings to a public authority for approval, or seal engineering work for public and private clients.".[16]This requirement is enforced by state and provincial legislation such as Quebec's Engineers Act.[17]In other countries, no such legislation exists. In Australia, state licensing of engineers is limited to the state of Queensland. Practically all certifying bodies maintain a code of ethics that they expect all members to abide by or risk expulsion.[18] In this way, these organizations play an important role in maintaining ethical standards for the profession. Even in jurisdictions where certification has little or no legal bearing on work, engineers are subject to contract law. In cases where an engineer's work fails he or she may be subject to the tort of negligence and, in extreme cases, thecharge of criminal negligence.[citation needed] An engineer's work must also comply with numerous other rules and regulations such as building codes and legislation pertaining to environmental law.CareersThere is no one typical career path for civil engineers. Most people who graduate with civil engineering degrees start with jobs that require a low level of responsibility, and as the new engineers prove their competence, they are trusted with tasks that have larger consequences and require a higher level of responsibility. However, within each branch of civil engineering career path options vary. In some fields and firms, entry-level engineers are put to work primarily monitoring construction in the field, serving as the "eyes and ears" of senior design engineers; while in other areas, entry-level engineers perform the more routine tasks of analysis or design and interpretation. Experienced engineers generally do more complex analysis or design work, or management of more complex design projects, or management of other engineers, or into specialized consulting, including forensic engineering.In general, civil engineering is concerned with the overall interface of human created fixed projects with the greater world. General civil engineers work closely with surveyors and specialized civil engineers to fit and serve fixed projects within their given site, community and terrain by designing grading, drainage, pavement, water supply, sewer service, electric and communications supply, and land divisions. General engineers spend much of their time visiting project sites, developing community consensus, and preparing construction plans. General civil engineering is also referred to as site engineering, a branch of civil engineering that primarily focuses on converting a tract of land from one usage to another. Civil engineers typically apply the principles of geotechnical engineering, structural engineering, environmental engineering, transportation engineering and construction engineering toresidential, commercial, industrial and public works projects of all sizes and levels of construction翻译：土木工程土木工程是一个专业的工程学科，包括设计，施工和维护与环境的改造，涉及了像桥梁，道路，河渠，堤坝和建筑物工程交易土木工程是最古老的军事工程后，工程学科，它被定义为区分军事工程非军事工程的学科它传统分解成若干子学科包括环境工程，岩土工程，结构工程，交通工程，市或城市工程，水资源工程，材料工程，海岸工程，勘测和施工工程等土木工程的范围涉及所有层次：从市政府到国家，从私人部门到国际公司。
【设计】土木工程毕业设计英语论文及翻译
【关键字】设计土木工程毕业设计英语论文及翻译篇一：土木工程毕业设计外文文献翻译外文文献翻译Reinforced ConcreteConcrete and reinforced concrete are used as building materials in every country. In many, including the United States and Canada, reinforced concrete is a dominant structural material in engineered construction. The universal nature of reinforced concrete construction stems from the wide availability of reinforcing bars and the constituents of concrete, gravel, sand, and cement, the relatively simple skills required in concrete construction, and the economy of reinforced concrete compared to other forms of construction. Concrete and reinforced concrete are used in bridges, buildings of all sorts underground structures, water tanks, television towers, offshore oil exploration and production structures, dams, and even in ships.Reinforced concrete structures may be cast-in-place concrete, constructed in their final location, or they may be precast concrete produced in a factory and erected at the construction site. Concrete structures may be severe and functional in design, or the shape and layout and be whimsical and artistic. Few other building materials off the architect and engineer such versatility and scope.Concrete is strong in compression but weak in tension. As a result, cracks develop whenever loads, or restrained shrinkage of temperature changes, give rise to tensile stresses in excess of the tensile strength of the concrete. In a plain concrete beam, the moments about the neutral axis due to applied loads are resisted by an internal tension-compression couple involving tension in the concrete. Such a beam fails very suddenly and completely when the first crack forms. In a reinforced concrete beam, steel bars are embedded in the concrete in such a way that the tension forces needed for moment equilibrium after the concrete cracks can be developed in the bars.The construction of a reinforced concrete member involves building a from of mold in the shape of the member being built. The form must be strong enough to support both the weight and hydrostatic pressure of the wet concrete, and any forces applied to it by workers, concrete buggies, wind, and so on. The reinforcement is placed in this form and held in place during the concreting operation. After the concrete has hardened, the forms are removed. As the forms are removed, props of shores are installed to support the weight of the concrete until it has reached sufficient strength to support the loads by itself.The designer must proportion a concrete member for adequate strength to resist the loads and adequate stiffness to prevent excessive deflections. In beam must be proportioned so that it can be constructed. For example, the reinforcement must be detailed so that it can be assembled in the field, and since the concrete is placed in the form after the reinforcement is in place, theconcrete must be able to flow around, between, and past the reinforcement to fill all parts of the form completely.The choice of whether a structure should be built of concrete, steel, masoy, or timber depends on the availability of materials and on a number of value decisions. The choice of structural system is made by the architect of engineer early in the design, based on the following considerations:1. Economy. Frequently, the foremost consideration is the overall const of the structure. This is, of course, a function of the costs of the materials and the labor necessary to erect them. Frequently, however, the overall cost is affected as much or more by the overall construction time since the contractor and owner must borrow or otherwise allocate money to carry out the construction and will not receive a return on this investment until the building is ready for occupancy. In a typical large apartment of commercial project, the cost of construction financing will be a significant fraction of the total cost. As a result, financial savings due to rapid construction may more than offset increased material costs. For this reason, any measures the designer can take to standardize the design and forming will generally pay off in reduced overall costs.In many cases the long-term economy of the structure may be more important than the first cost. As a result, maintenance and durability are important consideration.2. Suitability of material for architectural and structural function.A reinforced concrete system frequently allows the designer to combine the architectural and structural functions. Concrete has the advantage that it is placed in a plastic condition and is given the desired shapeand texture by means of the forms and the finishing techniques. This allows such elements ad flat plates or other types of slabs to serve as load-bearing elements while providing the finished floor and / or ceiling surfaces. Similarly, reinforced concrete walls can provide architecturally attractive surfaces in addition to having the ability to resist gravity, wind, or seismic loads. Finally, the choice of size of shape is governed by the designer and not by the availability of standard manufactured members.3. Fire resistance. The structure in a building must withstand the effects of a fire and remain standing while the building is evacuated and the fire is extinguished. A concrete building inherently has a 1- to 3-hour fire rating without special fireproofing or other details. Structural steel or timber buildings must be fireproofed to attain similar fire ratings.4. Low maintenance. Concrete members inherently require less maintenance than do structural steel or timber members. This is particularly true if dense, air-entrained concrete has been used for surfaces exposed to the atmosphere, and if care has been taken in the design to provide adequate drainage off and away from the structure. Special precautions must be taken for concrete exposed to salts such as deicing chemicals.5. Availability of materials. Sand, gravel, cement, and concrete mixing facilities are verywidely available, and reinforcing steel can be transported to most job sites more easily than can structural steel. As a result, reinforced concrete is frequently used in remote areas.On the other hand, there are a number of factors that may cause one to select a material other than reinforced concrete. These include:1. Low tensile strength. The tensile strength concrete is much lower than its compressive strength ( about 1/10 ), and hence concrete is subject to cracking. In structural uses this is overcome by using reinforcement to carry tensile forces and limit crack widths to within acceptable values. Unless care is taken in design and construction, however, these cracks may be unsightly or may allow penetration of water. When this occurs, water or chemicals such as road deicing salts may cause deterioration or staining of the concrete. Special design details are required in such cases. In the case of water-retaining structures, special details and / of prestressing are required to prevent leakage.2. Forms and shoring. The construction of a cast-in-place structure involves three steps not encountered in the construction of steel or timber structures. These are ( a ) the construction of the forms, ( b ) the removal of these forms, and (c) propping or shoring the new concrete to support its weight until its strength is adequate. Each of these steps involves labor and / or materials, which are not necessary with other forms of construction.3. Relatively low strength per unit of weight for volume. The compressive strength of concrete is roughly 5 to 10% that of steel, while its unit density is roughly 30% that of steel. As a result, a concrete structure requires a larger volume and a greater weight of material than does a comparable steel structure. As a result, long-span structures are often built from steel.4. Time-dependent volume changes. Both concrete and steel undergo-approximately the same amount of thermal expansion and contraction. Because there is less mass of steel to be heated or cooled, and because steel is a better concrete, a steel structure is generally affected by temperature changes to a greater extent than is a concrete structure. On the other hand, concrete undergoes frying shrinkage, which, if restrained, may cause deflections or cracking. Furthermore, deflections will tend to increase with time, possibly doubling, due to creep of the concrete under sustained loads.In almost every branch of civil engineering and architecture extensive use is made of reinforced concrete for structures and foundations. Engineers and architects requires basic knowledge of reinforced concrete design throughout their professional careers. Much of this text is directly concerned with the behavior and proportioning of components that make up typical reinforced concrete structures-beams, columns, and slabs. Once the behavior of these individual elements is understood, the designer will have the background to analyze and design a wide range of complex structures, such as foundations, buildings, and bridges, composed of these elements.Since reinforced concrete is a no homogeneous material that creeps, shrinks, and cracks, its stresses cannot be accurately predicted by the traditional equations derived in a course instrength of materials forhomogeneous elastic materials. Much of reinforced concrete design in therefore empirical, i.e., design equations and design methods are based on experimental and time-proved results instead of being derived exclusively from theoretical formulations.A thorough understanding of the behavior of reinforced concrete will allow the designer to convert an otherwise brittle material into tough ductile structural elements and thereby take advantage of concrete’s desirable characteristics, its high compressive strength, its fire resistance, and its durability.Concrete, a stone like material, is made by mixing cement, water, fine aggregate ( often sand ), coarse aggregate, and frequently other additives ( that modify properties ) into a workable mixture. In its unhardened or plastic state, concrete can be placed in forms to produce a large variety of structural elements. Although the hardened concrete by itself, i.e., without any reinforcement, is strong in compression, it lacks tensile strength and therefore cracks easily. Because ueinforced concrete is brittle, it cannot undergo large deformations under load and fails suddenly-without warning. The addition fo steel reinforcement to the concrete reduces the negative effects of its two principal inherent weaknesses, its susceptibility to cracking and its brittleness. When the reinforcement is strongly bonded to the concrete, a strong, stiff, and ductile construction material is produced. This material, called reinforced concrete, is used extensively to construct foundations, structural frames, storage takes, shell roofs, highways, walls, dams, canals, and innumerable other structures and building products. Two other characteristics of concrete that are present even when concrete is reinforced are shrinkage and creep, but the negative effects of these properties can be mitigated by careful design.A code is a set technical specifications and standards that control important details of design and construction. The purpose of codes it produce structures so that the public will be protected from poor of inadequate and construction.Two types f coeds exist. One type, called a structural code, is originated and controlled by specialists who are concerned with the proper use of a specific material or who are involved with the safe design of a particular class of structures.篇二：土木工程毕业设计中英文翻译附录：中英文翻译英文部分：LOADSLoads that act on structures are usually classified as dead loads or live loads.Dead loads are fixed in location and constant in magnitude throughout the life of the ually the self-weight of a structure is the most important part of the structure and the unit weight of the material.Concrete density varies from about 90 to 120 pcf (14 to 19 KN/m2)for lightweight concrete,and is about 145 pcf (23 KN/mKN/m2)for normal concrete.In calculating the dead load of structural concrete,usually a 5pcf (1 )increment is included with the weight of the concrete to account for the presence of the 2 reinforcement.Live loads are loads such as occupancy,snow,wind,or traffic loads,or seismic forces.They may be either fully or partially in place,or not present at all.They may also change in location.Althought it is the responsibility of the engineer to calculate dead loads,live loads are usually specified by local,regional,or national codes and specifications.Typical sources are the publications of the American National Standards Institute,the American Association of State Highway and Transportation Officials and,for wind loads,the recommendations of the ASCE Task Committee on Wind Forces.Specified live the loads usually include some allowance for overload,and may include measures such as posting of maximum loads will not be exceeded.It is oftern important to distinguish between the specified load,and what is termed the characteristic load,that is,the load that actually is in effect under normal conditions of service,which may be significantly less.In estimating the long-term deflection of a structure,for example,it is the characteristic load that is important,not the specified load.The sum of the calculated dead load and the specified live load is called the service load,because this is the maximum load which may reasonably be expected to act during the service resisting is a multiple of the service load.StrengthThe strength of a structure depends on the strength of the materials from which it is made.Minimum material strengths are specified in certain standardized ways.The properties of concrete and its components,the methods of mixing,placing,and curing to obtain the required quality,and the methods for testing,are specified by the American Concrete Insititue(ACI).Included by refrence in the same documentare standards of the American Society for Testing Materials(ASTM)pertaining to reinforcing and prestressing steels and concrete.Strength also depends on the care with which the structure is built.Member sizes may differ from specified dimensions,reinforcement may be out of position,or poor placement of concrete may result in voids.An important part of the job of the ergineer is to provide proper supervision of construction.Slighting of this responsibility has had disastrous consequences in more than one instance.Structural SafetySafety requires that the strength of a structure be adequate for all loads that may conceivably act on it.If strength could be predicted accurately and if loads were known with equal certainty,then safely could be assured by providing strength just barely in excess of the requirements of the loads.But there are many sources of uncertainty in the estimation of loads as well as in analysis,design,and construction.These uncertainties require a safety margin.In recent years engineers have come to realize that the matter of structural safety isprobabilistic in nature,and the safety provisions of many current specifications reflect this view.Separate consideration is given to loads and strength.Load factors,larger than unity,are applied to the calculated dead loads and estimated or specified service live loads,to obtain factorde loads that the member must just be capable of sustaining at incipient failure.Load factors pertaining to different types of loads vary,depending on the degree of uncertainty associated with loads of various types,and with the likelihood of simultaneous occurrence of different loads.Early in the development of prestressed concrete,the goal of prestressing was the complete elimination of concrete ternsile stress at service loads.The concept was that of an entirely new,homogeneous material that woukd remain uncracked and respond elastically up to the maximum anticipated loading.This kind of design,where the limiting tensile stressing,while an alternative approach,in which a certain amount of tensile amount of tensile stress is permitted in the concrete at full service load,is called partial prestressing.There are cases in which it is necessary to avoid all risk of cracking and in which full prestressing is required.Such cases include tanks or reservious where leaks must be avoided,submerged structures or those subject to a highly corrosive envionment where maximum protection of reinforcement must be insured,and structures subject to high frequency repetition of load where faatigue of the reinforcement may be a consideration.However,there are many cses where substantially improved performance,reduced cost,or both may be obtained through the use of a lesser amount of prestress.Full predtressed beams may exhibit an undesirable amount of upward camber because of the eccentric prestressing force,a displacement that is only partially counteracted by the gravity loads producing downward deflection.This tendency is aggrabated by creep in the concrete,which magnigies the upward displacement due to the prestress force,but has little influence on the should heavily prestressed members be overloaded and fail,they may do so in a brittle way,rather than gradually as do beams with a smaller amount of prestress.This is important from the point of view of safety,because suddenfailure without warning is dangeroud,and gives no opportunity for corrective measures to be taken.Furthermore,experience indicates that in many cases improved economy results from the use of a combination of unstressed bar steel and high strength prestressed steel tendons.While tensile stress and possible cracking may be allowed at full service load,it is also recognized that such full service load may be infrequently applied.The typical,or characteristic,load acting is likely to be the dead load plus a small fraction of the specified live load.Thus a partially predtressed beam may not be subject to tensile stress under the usual conditions of loading.Cracks may from occasionally,when the maximum load is applied,but these will close completely when that load is removed.They may be no more objectionable in prestressed structures than in ordinary reinforced.They may be no more objectionable in prestressed structures than in ordinary reinforced concrete,in which flexural cracks alwaysform.They may be considered a small price for the improvements in performance and economy that are obtained.It has been observed that reinforced concrete is but a special case of prestressed concrete in which the prestressing force is zero.The behavior of reinforced and prestressed concrete beams,as the failure load is approached,is essentially the same.The Joint European Committee on Concrete establishes threee classes of prestressed beams.Class 1:Fully prestressed,in which no tensile stress is allowed in the concrete at service load.Class 2:Partially prestressed, in which occasional temporary cracking is permitted under infrequent high loads.Class 3:Partially prestressed,in which there may be permanent cracks provided that their width is suitably limited.The choise of a suitable amount of prestress is governed by a variety of factors.These include thenature of the loading (for exmaple,highway or railroad bridged,storage,ect.),the ratio of live to dead load,the frequency of occurrence of loading may be reversed,such as in transmission poles,a high uniform prestress would result ultimate strength and in brittle failure.In such a case,partial prestressing provides the only satifactory solution.The advantages of partial prestressing are important.A smaller prestress force will be required,permitting reduction in the number of tendons and anchorages.The necessary flexural strength may be provided in such cases either by a combination of prestressed tendons and non-prestressed reinforcing bars,or by an adequate number of high-tensile tendons prestredded to level lower than the prestressing force is less,the size of the bottom flange,which is requied mainly to resist the compression when a beam is in the unloaded stage,can be reduced or eliminated altogether.This leads in turn to significant simplification and cost reduction in the construction of forms,as well as resulting in structures that are mor pleasing esthetically.Furthermore,by relaxing the requirement for low service load tension in the concrete,a significant improvement can be made in the deflection characteristics of a beam.Troublesome upward camber of the member in the unloaded stage fan be avoeded,and the prestress force selected primarily to produce the desired deflection for a particular loading condition.The behavior of partially prestressed beamsm,should they be overloaded to failure,is apt to be superior to that of fully prestressed beams,because the improved ductility provides ample warning of distress.英译汉：荷载作用在结构上的荷载通常分为恒载或活载。
土木工程专业毕业设计外文文献翻译2篇
土木工程专业毕业设计外文文献翻译2篇XXXXXXXXX学院学士学位毕业设计（论文）英语翻译课题名称英语翻译学号学生专业、年级所在院系指导教师选题时间Fundamental Assumptions for Reinforced ConcreteBehaviorThe chief task of the structural engineer is the design of structures. Design is the determination of the general shape and all specific dimensions of a particular structure so that it will perform the function for which it is created and will safely withstand the influences that will act on it throughout useful life. These influences are primarily the loads and other forces to which it will be subjected, as well as other detrimental agents, such as temperature fluctuations, foundation settlements, and corrosive influences, Structural mechanics is one of the main tools in this process of design. As here understood, it is the body of scientific knowledge that permits one to predict with a good degree of certainly how a structure of give shape and dimensions will behave when acted upon by known forces or other mechanical influences. The chief items of behavior that are of practical interest are (1) the strength of the structure, i. e. , that magnitude of loads of a give distribution which will cause the structure to fail, and (2) the deformations, such as deflections and extent of cracking, that the structure will undergo when loaded underservice condition.The fundamental propositions on which the mechanics of reinforced concrete is based are as follows:1.The internal forces, such as bending moments, shear forces, and normal andshear stresses, at any section of a member are in equilibrium with the effect of the external loads at that section. This proposition is not an assumption but a fact, because any body or any portion thereof can be at rest only if all forces acting on it are in equilibrium.2.The strain in an embedded reinforcing bar is the same as that of thesurrounding concrete. Expressed differently, it is assumed that perfect bonding exists between concrete and steel at the interface, so that no slip can occur between the two materials. Hence, as the one deforms, so must the other. With modern deformed bars, a high degree of mechanical interlocking is provided in addition to the natural surface adhesion, so this assumption is very close to correct.3.Cross sections that were plane prior to loading continue to be plan in themember under load. Accurate measurements have shown that when a reinforced concrete member is loaded close to failure, this assumption is not absolutely accurate. However, the deviations are usually minor.4.In view of the fact the tensile strength of concrete is only a small fraction ofits compressive strength; the concrete in that part of a member which is in tension is usually cracked. While these cracks, in well-designed members, are generally so sorrow as to behardly visible, they evidently render the cracked concrete incapable of resisting tension stress whatever. This assumption is evidently a simplification of the actual situation because, in fact, concrete prior to cracking, as well as the concrete located between cracks, does resist tension stresses of small magnitude. Later in discussions of the resistance of reinforced concrete beams to shear, it will become apparent that under certain conditions this particular assumption is dispensed with and advantage is taken of the modest tensile strength that concrete can develop.5.The theory is based on the actual stress-strain relation ships and strengthproperties of the two constituent materials or some reasonable equivalent simplifications thereof. The fact that novelistic behavior is reflected in modern theory, that concrete is assumed to be ineffective in tension, and that the joint action of the two materials is taken into consideration results in analytical methods which are considerably more complex and also more challenging, than those that are adequate for members made of a single, substantially elastic material.These five assumptions permit one to predict by calculation the performance of reinforced concrete members only for some simple situations. Actually, the joint action of two materials as dissimilar and complicated as concrete and steel is so complex that it has not yet lent itself to purely analytical treatment. For this reason, methods of design and analysis, while using these assumptions, are very largely based on the results of extensive and continuing experimental research. They are modified and improved as additional test evidence becomes available.钢筋混凝土的基本假设作为结构工程师的主要任务是结构设计。
土木工程专业英语课文原文及对照翻译
Civil EngineeringCivil engineering, the oldest of the engineering specialties, is the planning, design, construction, and management of the built environment. This environment includes all structures built according to scientific principles, from irrigation and drainage systems to rocket-launching facilities.土木工程学作为最老的工程技术学科,是指规划,设计,施工及对建筑环境的管理;此处的环境包括建筑符合科学规范的所有结构,从灌溉和排水系统到火箭发射设施;Civil engineers build roads, bridges, tunnels, dams, harbors, power plants, water and sewage systems, hospitals, schools, mass transit, and other public facilities essential to modern society and large population concentrations. They also build privately owned facilities such as airports, railroads, pipelines, skyscrapers, and other large structures designed for industrial, commercial, or residential use. In addition, civil engineers plan, design, and build complete cities and towns, and more recently have been planning and designing space platforms to house self-contained communities.土木工程师建造道路,桥梁,管道,大坝,海港,发电厂,给排水系统,医院,学校,公共交通和其他现代社会和大量人口集中地区的基础公共设施;他们也建造私有设施,比如飞机场,铁路,管线,摩天大楼,以及其他设计用作工业,商业和住宅途径的大型结构;此外,土木工程师还规划设计及建造完整的城市和乡镇,并且最近一直在规划设计容纳设施齐全的社区的空间平台;The word civil derives from the Latin for citizen. In 1782, Englishman John Smeaton used the term to differentiate his nonmilitary engineering work from that of the military engineers who predominated at the time. Since then, the term civil engineering has often been used to refer to engineers who build public facilities, although the field is much broader土木一词来源于拉丁文词“公民”;在1782年,英国人John Smeaton为了把他的非军事工程工作区别于当时占优势地位的军事工程师的工作而采用的名词;自从那时起,土木工程学被用于提及从事公共设施建设的工程师,尽管其包含的领域更为广阔;Scope. Because it is so broad, civil engineering is subdivided into a number of technical specialties. Depending on the type of project, the skills of many kinds of civil engineer specialists may be needed. When a project begins, the site is surveyed and mapped by civil engineers who locate utility placement—water, sewer, and power lines. Geotechnical specialists perform soil experiments to determine if the earth can bear the weight of the project. Environmental specialists study the project’s impact on the local area: the potential for air and groundwater pollution, the project’s impact on local animal and plant life, and how the project can be designed to me et government requirements aimed at protecting the environment. Transportation specialists determine what kind of facilities are needed to ease the burden on local roads and other transportation networks that will result from the completed project. Meanwhile, structural specialists use preliminary data to make detailed designs, plans, and specifications for the project. Supervising and coordinating the work of these civil engineer specialists, from beginning to end of the project, are the construction management specialists. Based on information supplies by the other specialists, construction management civil engineers estimate quantities and costs of materials and labor, schedule all work, order materials and equipment for the job, hire contractors and subcontractors, and perform other supervisory work to ensure the project is completed on time and as specified.领域;因为包含范围太广,土木工程学又被细分为大量的技术专业;不同类型的工程需要多种不同土木工程专业技术;一个项目开始的时候,土木工程师要对场地进行测绘,定位有用的布置,如地下水水位,下水道,和电力线;岩土工程专家则进行土力学试验以确定土壤能否承受工程荷载;环境工程专家研究工程对当地的影响,包括对空气和地下水的可能污染,对当地动植物生活的影响,以及如何让工程设计满足政府针对环境保护的需要;交通工程专家确定必需的不同种类设施以减轻由整个工程造成的对当地公路和其他交通网络的负担;同时,结构工程专家利用初步数据对工程作详细规划,设计和说明;从项目开始到结束,对这些土木工程专家的工作进行监督和调配的则是施工管理专家;根据其他专家所提供的信息,施工管理专家计算材料和人工的数量和花费,所有工作的进度表,订购工作所需要的材料和设备,雇佣承包商和分包商,还要做些额外的监督工作以确保工程能按时按质完成;Throughout any given project, civil engineers make extensive use of computers. Computers are used to design the project’s various elements computer-aided design, or CAD and to manage it. Computers are necessity for the modern civil engineer because they permit the engineer to efficiently handle the large quantities of data needed in determining the best way to construct a project.贯穿任何给定项目,土木工程师都需要大量使用计算机;计算机用于设计工程中使用的多数元件即计算机辅助设计,或者CAD并对其进行管理;计算机成为了现代土木工程师的必备品,因为它使得工程师能有效地掌控所需的大量数据从而确定建造一项工程的最佳方法; Structural engineering. In this specialty, civil engineers plan and design structures of all types, including bridge, dams, power plants, supports for equipment, special structures for offshore projects, the United States space program, transmission towers, giant astronomical and radio telescopes, and many other kinds of projects. Using computers, structural engineers determine the forces a structure must resist: its own weight, wind and hurricane forces, temperature changes that expand or contract construction materials, and earthquakes. They also determine the combination of appropriate materials: steel, concrete, plastic, asphalt, brick, aluminum, or other construction materials.结构工程学;在这一专业领域,土木工程师规划设计各种类型的结构,包括桥梁,大坝,发电厂,设备支撑,海面上的特殊结构,美国太空计划,发射塔,庞大的天文和无线电望远镜,以及许多其他种类的项目;结构工程师应用计算机确定一个结构必须承受的力：自重,风荷载和飓风荷载,建筑材料温度变化引起的胀缩,以及地震荷载;他们也需确定不同种材料如钢筋,混凝土,塑料,石头,沥青,砖,铝或其他建筑材料等的复合作用;Water resources engineering. Civil engineers in this specialty deal with all aspects of the physical control of water. Their projects help prevent floods, supply water for cities and for irrigation, manage and control rivers and water runoff, and maintain beaches and other waterfront facilities. In addition, they design and maintain harbors, canals, and locks, build huge hydroelectric dams and smaller dams and water impoundments of all kinds, help design offshore structures, and determine the location of structures affecting navigation.水利工程学;土木工程师在这一领域主要处理水的物理控制方面的种种问题;他们的项目用于帮助预防洪水灾害,提供城市用水和灌溉用水,管理控制河流和水流物,维护河滩及其他滨水设施;此外,他们设计和维护海港,运河与水闸,建造大型水利大坝与小型坝,以及各种类型的围堰,帮助设计海上结构并且确定结构的位置对航行影响;Geotechnical engineering. Civil engineers who specialize in this field analyze the properties of soils and rocks that support structures and affect structural behavior. They evaluate and work to minimize the potential settlement of buildings and other structures that stems from the pressure of their weight on the earth. These engineers also evaluate and determine how to strengthen the stability of slopes and fills and how to protect structures against earthquakes and the effects ofgroundwater.岩土工程学;专业于这个领域的土木工程师对支撑结构并影响结构行为的土壤和岩石的特性进行分析;他们计算建筑和其他结构由于自重压力可能引起的沉降,并采取措施使之减少到最小;他们也需计算并确定如何加强斜坡和填充物的稳定性以及如何保护结构免受地震和地下水的影响;Environmental engineering. In this branch of engineering, civil engineers design, build and supervise systems to provide safe drinking water and to prevent and control pollution of water supplies, both on the surface and underground. They also design, build, and supervise projects to control or eliminate pollution of the land and air. These engineers build water and wastewater treatment plants, and design air scrubbers and other devices to minimize or eliminate air pollution caused by industrial processes, incineration, or other smoke-producing activities. They also work to control toxic and hazardous wastes through the construction of special dump sites or the neutralizing of toxic and hazardous substances. In addition, the engineers design and manage sanitary landfills to prevent pollution of surrounding land.环境工程学;在这一工程学分支中,土木工程师设计,建造并监视系统以提供安全的饮用水,同时预防和控制地表和地下水资源供给的污染;他们也设计,建造并监视工程以控制甚至消除对土地和空气的污染;他们建造供水和废水处理厂,设计空气净化器和其他设备以最小化甚至消除由工业加工、焚化及其他产烟生产活动引起的空气污染;他们也采用建造特殊倾倒地点或使用有毒有害物中和剂的措施来控制有毒有害废弃物;此外,工程师还对垃圾掩埋进行设计和管理以预防其对周围环境造成污染;Transportation engineering. Civil engineers working in this specialty build facilities to ensure safe and efficient movement of both people and goods. They specialize in designing and maintaining all types of transportation facilities, highways and streets, mass transit systems, railroads and airfields, ports and harbors. Transportation engineers apply technological knowledge as well as consideration of the economic, political, and social factors in designing each project. They work closely with urban planners, since the quality of the community is directly related to the quality of the transportation system.交通工程学;从事这一专业领域的土木工程师建造可以确保人和货物安全高效运行的设施;他们专门研究各种类型运输设施的设计和维护,如公路和街道,公共交通系统,铁路和飞机场,港口和海港;交通工程师应用技术知识及考虑经济,政治和社会因素来设计每一个项目;他们的工作和城市规划者十分相似,因为交通运输系统的质量直接关系到社区的质量;Pipeline engineering. In this branch of civil engineering, engineers build pipelines and related facilities which transport liquids, gases, or solids ranging from coal slurries mixed coal and water and semiliquid wastes, to water, oil, and various types of highly combustible and noncombustible gases. The engineers determine pipeline design, the economic and environmental impact of a project on regions it must traverse, the type of materials to be used-steel, concrete, plastic, or combinations of various materials-installation techniques, methods for testing pipeline strength, and controls for maintaining proper pressure and rate of flow of materials being transported. When hazardous materials are being carried, safety is a major consideration as well.渠道工程学;在土木工程学的这一支链中,土木工程师建造渠道和运送从煤泥浆混合的煤和水和半流体废污,到水、石油和多种类型的高度可燃和不可燃的气体中分离出来的液体,气体和固体的相关设备;工程师决定渠道的设计,项目所处地区必须考虑到的经济性和环境因素,以及所使用材料的类型——钢、混凝土、塑料、或多种材料的复合——的安装技术,测试渠道强度的方法,和控制所运送流体材料保持适当的压力和流速;当流体中携带危险材料时,安全性因素也需要被考虑;Construction engineering. Civil engineers in this field oversee the construction of a project from beginning to end. Sometimes called project engineers, they apply both technical and managerial skills, including knowledge of construction methods, planning, organizing, financing, and operating construction projects. They coordinate the activities of virtually everyone engaged in the work: the surveyors; workers who lay out and construct the temporary roads and ramps, excavate for the foundation, build the forms and pour the concrete; and workers who build the steel framework. These engineers also make regular progress reports to the owners of the structure.建筑工程学;土木工程师在这个领域中从开始到结束监督项目的建筑;他们,有时被称为项目工程师,应用技术和管理技能,包括建筑工艺,规划,组织,财务,和操作项目建设的知识;事实上,他们协调工程中每个人的活动：测量员,布置和建造临时道路和斜坡,开挖基础,支模板和浇注混凝土的工人,以及钢筋工人;这些工程师也向结构的业主提供进度计划报告;Community and urban planning. Those engaged in this area of civil engineering may plan and develop community within a city, or entire cities. Such planning involves far more than engineering consideration; environmental, social, and economic factors in the use and development of land and natural resources are also key elements. These civil engineers coordinate planning of public works along with private development. They evaluate the kinds of facilities needed, including streets and highways, public transportation systems, airports, port facilities, water-supply and waste water-disposal systems, public buildings, parks, and recreational and other facilities to ensure social and economic as well as environmental well-being.社区和城市规划;从事土木工程这一方面的工程师可能规划和发展一个城市中的社区,或整个城市;此规划中所包括的远远不仅仅为工程因素,土地的开发使用和自然资源环境的,社会的和经济的因素也是主要的成分;这些土木工程师对公共建设工程的规划和私人建筑的发展进行协调;他们评估所需的设施,包括街道,公路,公共运输系统,机场,港口,给排水和污水处理系统,公共建筑,公园,和娱乐及其他设施以保证社会,经济和环境地协调发展; Photogrametry, surveying, and mapping. The civil engineers in this specialty precisely measure the Earth’s surface to obtain reliable information for locating and designing engineering projects. This practice often involves high-technology methods such as satellite and aerial surveying, and computer-processing of photographic imagery. Radio signal from satellites, scans by laser and sonic beams, are converted to maps to provide far more accurate measurements for boring tunnels, building highways and dams, plotting flood control and irrigation project, locating subsurface geologic formations that may affect a construction project, and a host of other building uses.摄影测量,测量学和地图绘制;在这一专业领域的土木工程师精确测量地球表面以获得可靠的信息来定位和设计工程项目;这一方面包括高工艺学方法,如卫星成相,航拍,和计算机成相;来自人造卫星的无线电信号,通过激光和音波柱扫描被转换为地图,为隧道钻孔,建造高速公路和大坝,绘制洪水控制和灌溉方案,定位可能影响建筑项目的地下岩石构成,以及许多其他建筑用途提供更精准的测量;Other specialties. Two additional civil engineering specialties that are not entirely within the scope of civil engineering but are essential to the discipline are engineering management and engineering teaching.其他的专门项目;还有两个并不完全在土木工程范围里面但对训练相当重要的附加的专门项目是工程管理和工程教学;Engineering management. Many civil engineers choose careers that eventually lead to management. Others are able to start their careers in management positions. The civilengineer-manager combines technical knowledge with an ability to organize and coordinate worker power, materials, machinery, and money. These engineers may work in government—municipal, county, state, or federal; in the . Army Corps of Engineers as military or civilian management engineers; or in semiautonomous regional or city authorities or similar organizations. They may also manage private engineering firms ranging in size from a few employees to hundreds.工程管理;许多土木工程师都选择最终通向管理的职业;其他则能让他们的事业从管理位置开始;土木工程管理者结合技术上的知识和一种组织能力来协调劳动力,材料,机械和钱;这些工程师可能工作在政府——市政、国家、州或联邦；在美国陆军军团作为军队或平民的管理工程师；或在半自治地区,城市主管当局或相似的组织;他们也可能管理规模为从几个到百个雇员的私营工程公司;Engineering teaching. The civil engineer who chooses a teaching career usually teaches both graduate and undergraduate students in technical specialties. Many teaching civil engineers engage in basic research that eventually leads to technical innovations in construction materials and methods. Many also serve as consultants on engineering projects, or on technical boards and commissions associated with major projects.工程教学;通常选择教学事业的土木工程师教授研究生和本科生技术上的专门项目;许多从事教学的土木工程师参与会导致建筑材料和施工方法技术革新的基础研究;多数也担任工程项目或技术领域的顾问,和主要项目的代理;。
土木工程概论论文外文翻译
ntroduction to Civil Engineering PapersCivil Engineering for the development of a key role, first as a material foundation for the civil engineering construction materials, followed by the subsequent development of the design theory and construction technology. Every time a new quality of building materials, civil engineering will be a leap-style development.People can only rely on the early earth, wood and other natural materials in the construction activities, and later appeared in brick and tile that artificial materials, so that the first human to break the shackles of natural building materials. China in the eleventh century BC in the early Western Zhou Dynasty created the tile. The first brick in the fifth century BC to the third century BC, when the tomb of the Warring States Period. Brick and tile better than the mechanical properties of soil, materials, and easy to manufacture.The brick and tile so that people began to appear widely, to a large number of housing construction and urban flood control project, and so on. This civil engineering technology has been rapid development. Up to 18 to the 19th century, as long as two thousand years, brick and tile has been a major civil engineering construction materials, human civilization has made a great contribution to the even was also widely used in the present.The application of a large number of steel products is the second leap in civil engineering. Seventeen 1970s the use of pig iron, the early nineteenth century, the use of wrought iron bridges and the construction of housing, which is a prelude to the emergence of steel.From the beginning of the mid-nineteenth century, metallurgical industry, smelting and rolling out high tensile and compressive strength, ductility, uniformity of the quality of construction steel and then produce high-strength steel wire, steel cables. As a result of the need to adapt to the development of the steel structure have been flourishing. In addition to the application of the original beam, arch structure, the new truss, aframework, the structure of network, cable structures to promote the gradual emergence of the structure of Yan in the form of flowers.From the brick building long-span structures, stone structures, a few meters of wood, steel structure to the development of tens of meters, a few hundred meters, until modern km above. So in the river, cross the bridge from shelves, on the ground since the construction of skyscrapers and high-rise tower, even in the laying of underground railway, to create an unprecedented miracle.In order to meet the needs of the development of steel works, on the basis of Newton's mechanics, material mechanics, structural mechanics, structural engineering design theory came into being, and so on. Construction machinery, construction technology and construction organization design theory also development, civil engineering from the experience of rising to become science, engineering practice and theoretical basis for both is a different place, which led to more rapid development of civil engineering.During the nineteenth century, 20, made of Portland cement, concrete has come out. Concrete can aggregate materials, easy-to-concrete structures forming, but the tensile strength of concrete is very small, limited use. By the middle of the nineteenth century, the surge in steel production, with the emergence of this new type of reinforced concrete composite construction materials, which bear the tension steel, concrete bear the pressure and play their own advantages. Since the beginning of the 20th century, reinforced concrete is widely used in various fields of civil engineering.From the beginning of the 1930s, there have been pre-stressed concrete. Pre-stressed concrete structure of the crack resistance, rigidity and carrying capacity, much higher than the reinforced concrete structure, which uses an even wider area. Civil Engineering into the reinforced concrete and prestressed concrete dominant historical period. Concrete buildings to bring about the emergence of new economic, aestheticstructure in the form of engineering, civil engineering so that a new construction technology and engineering design of the structure of the theory. This is another leap in the development of civil engineering.A project to build the facilities in general to go through the investigation, design and construction in three stages, require the use of geological prospecting projects, hydro-geological survey, engineering survey, soil mechanics, mechanical engineering, engineering design, building materials, construction equipment, engineering machinery, building the economy , And other disciplines and construction technology, construction and other fields of knowledge, as well as computer and mechanical testing techniques. Civil engineering is therefore a broad range of integrated disciplines. With the progress in science and technology development and engineering practice, the civil engineering disciplines have also been developed into a broad connotation, the number of categories, the structure of complex integrated system.Civil Engineering is accompanied by the development of human society developed. It works in the construction of facilities reflect the various historical periods of socio-economic, cultural, scientific, technological development outlook, which civil society has become one of the historical development of the witness.In ancient times, people began to build simple houses, roads, bridges and still water channel to meet the simple life and production. Later, in order to adapt to the war, production and dissemination of religious life, as well as the needs of the construction of the city, canals, palaces, temples and other buildings.Many well-known works shown in this historical period of human creativity. For example, the Great Wall of China, Dujiangyan, the Grand Canal, Zhaozhou Bridge, Yingxian Wooden Tower, the pyramids of Egypt, Greece's Parthenon, Rome's water supply project, colosseum amphitheater (Rome large animal fighting Field), as well as many other well-known churches, palaces and so on.After the industrial revolution, especially in the 20th century, on the one hand, civil society to put forward a new demand; On the other hand, all areas of society for the advancement of civil engineering to create good conditions. Thus this period of civil engineering has been advanced by leaps and bounds. All over the world there have been large-scale modernization of industrial plants, skyscrapers, nuclear power plants, highways and railways, long-span bridges, and large-diameter pipelines long tunnel, the Grand Canal, the big dams, airports, port and marine engineering, etc. . For civil engineering continually modern human society to create a new physical environment, human society, modern civilization has become an important part.Civil Engineering is a very practical subjects. In the early days, through the civil engineering practice, summing up successful experience, in particular, to draw lessons from the failure of developed. From the beginning of the 17th century, with Galileo and Newton as a pilot with the mechanics of the modern civil engineering practice, gradually formed the mechanical, structural mechanics, fluid mechanics, rock mechanics, civil engineering as the basis of theoretical subjects. This experience in civil engineering from the gradually developed into a science.In the course of the development of civil engineering, engineering practice often first experience in theory, engineering accidents often show a new unforeseen factors, triggering a new theory of the research and development. So far a number of projects dealing with the problem, is still very much rely on practical experience.Civil Engineering Technology with the main reason for the development of engineering practice and not by virtue of scientific experiments and theoretical studies, for two reasons: First, some of the objective situation is too complicated and difficult to faithfully carry out laboratory or field testing and analysis. For example, the foundation, tunnel and underground engineering and deformation of the state and its changes over time, still need to refer to an analysis of engineeringexperience to judge. Second, only a new engineering practice in order to reveal new problems. For example, the construction of a high-rise buildings, high-rise tower and mast-span bridges, wind and earthquake engineering problems highlighted in order to develop this new theory and technology.In the long-term civil engineering practice, it is not only building great attention to the arts, has made outstanding achievements; and other works, but also through the choice of different materials, such as the use of stone, steel and reinforced concrete, with natural Environmental art in the construction of a number of very beautiful, very functional and good works. Ancient Great Wall of China, the modern world, many of the television tower and the bridge ramp Zhang, are cases in point.翻译：土木工程概论论文对土木工程的发展起关键作用的，首先是作为工程物质基础的土木建筑材料，其次是随之发展起来的设计理论和施工技术。
土木工程英语文献原文及中文翻译
Civil engineering introduction papers[英语原文]Abstract: the civil engineering is a huge discipline, but the main one is building, building whether in China or abroad, has a long history, long-term development process. The world is changing every day, but the building also along with the progress of science and development. Mechanics findings, material of update, ever more scientific technology into the building. But before a room with a tile to cover the top of the house, now for comfort, different ideas, different scientific, promoted the development of civil engineering, making it more perfect.[key words] : civil engineering; Architecture; Mechanics, Materials.Civil engineering is build various projects collectively. It was meant to be and "military project" corresponding. In English the history of Civil Engineering, mechanical Engineering, electrical Engineering, chemical Engineering belong to to Engineering, because they all have MinYongXing. Later, as the project development of science and technology, mechanical, electrical, chemical has gradually formed independent scientific, to Engineering became Civil Engineering of specialized nouns. So far, in English, to Engineering include water conservancy project, port Engineering, While in our country, water conservancy projects and port projects also become very close and civil engineering relatively independent branch. Civil engineering construction of object, both refers to that built on the ground, underground water engineering facilities, also refers to applied materials equipment and conduct of the investigation, design and construction, maintenance, repair and other professional technology.Civil engineering is a kind of with people's food, clothing, shelter and transportation has close relation of the project. Among them with "live" relationship is directly. Because, to solve the "live" problem must build various types of buildings. To solve the "line, food and clothes" problem both direct side, but also a indirect side. "Line", must build railways, roads, Bridges, "Feed", must be well drilling water, water conservancy, farm irrigation, drainage water supply for the city, that is direct relation. Indirectly relationship is no matter what you do, manufacturing cars, ships, or spinning and weaving, clothing, or even production steel, launch satellites, conducting scientific research activities are inseparable from build various buildings, structures and build all kinds of project facilities.Civil engineering with the progress of human society and development, yet has evolved into large-scale comprehensive discipline, it has out many branch, such as: architectural engineering, the railway engineering, road engineering, bridge engineering, special engineering structure, waterand wastewater engineering, port engineering, hydraulic engineering, environment engineering disciplines. [1]Civil engineering as an important basic disciplines, and has its important attributes of: integrated, sociality, practicality, unity. Civil engineering for the development of national economy and the improvement of people's life provides an important material and technical basis, for many industrial invigoration played a role in promoting, engineering construction is the formation of a fixed asset basic production process, therefore, construction and real estate become in many countries and regions, economic powerhouses.Construction project is housing planning, survey, design, construction of the floorboard. Purpose is for human life and production provide places.Houses will be like a man, it's like a man's life planning environment is responsible by the planners, Its layout and artistic processing, corresponding to the body shape looks and temperament, is responsible by the architect, Its structure is like a person's bones and life expectancy, the structural engineer is responsible, Its water, heating ventilation and electrical facilities such as the human organ and the nerve, is by the equipment engineer is responsible for. Also like nature intact shaped like people, in the city I district planning based on build houses, and is the construction unit, reconnaissance unit, design unit of various design engineers and construction units comprehensive coordination and cooperation process.After all, but is structural stress body reaction force and the internal stress and how external force balance. Building to tackle, also must solve the problem is mechanical problems. We have to solve the problem of discipline called architectural mechanics. Architectural mechanics have can be divided into: statics, material mechanics and structural mechanics three mechanical system. Architectural mechanics is discussion and research building structure and component in load and other factors affecting the working condition of, also is the building of intensity, stiffness and stability. In load, bear load and load of structure and component can cause the surrounding objects in their function, and the object itself by the load effect and deformation, and there is the possibility of damage, but the structure itself has certain resistance to deformation and destruction of competence, and the bearing capacity of the structure size is and component of materials, cross section, and the structural properties of geometry size, working conditions and structure circumstance relevant. While these relationships can be improved by mechanics formula solved through calculation.Building materials in building and has a pivotal role. Building material is with human society productivity and science and technologyimproves gradually developed. In ancient times, the human lives, the line USES is the rocks andTrees. The 4th century BC, 12 ~ has created a tile and brick, humans are only useful synthetic materials made of housing. The 17th century had cast iron and ShouTie later, until the eighteenth century had Portland cement, just make later reinforced concrete engineering get vigorous development. Now all sorts of high-strength structural materials, new decoration materials and waterproof material development, criterion and 20th century since mid organic polymer materials in civil engineering are closely related to the widely application. In all materials, the most main and most popular is steel, concrete, lumber, masonry. In recent years, by using two kinds of material advantage, will make them together, the combination of structure was developed. Now, architecture, engineering quality fit and unfit quality usually adopted materials quality, performance and using reasonable or not have direct connection, in meet the same technical indicators and quality requirements, under the precondition of choice of different material is different, use method of engineering cost has direct impact.In construction process, building construction is and architectural mechanics, building materials also important links. Construction is to the mind of the designer, intention and idea into realistic process, from the ancient hole JuChao place to now skyscrapers, from rural to urban country road elevated road all need through "construction" means. A construction project, including many jobs such as dredging engineering, deep foundation pit bracing engineering, foundation engineering, reinforced concrete structure engineering, structural lifting project, waterproofing, decorate projects, each type of project has its own rules, all need according to different construction object and construction environment conditions using relevant construction technology, in work-site.whenever while, need and the relevant hydropower and other equipment composition of a whole, each project between reasonable organizing and coordination, better play investment benefit. Civil engineering construction in the benefit, while also issued by the state in strict accordance with the relevant construction technology standard, thus further enhance China's construction level to ensure construction quality, reduce the cost for the project.Any building built on the surface of the earth all strata, building weight eventually to stratum, have to bear. Formation Support building the rocks were referred to as foundation, and the buildings on the ground and under the upper structure of self-respect and liable to load transfer to the foundation of components or component called foundation. Foundation, and the foundation and the superstructure is a building of three inseparable part. According to the function is different, but in load, under the action of them are related to each other, is theinteraction of the whole. Foundation can be divided into natural foundation and artificial foundation, basic according to the buried depth is divided into deep foundation and shallow foundation. , foundation and foundation is the guarantee of the quality of the buildings and normal use close button, where buildings foundation in building under loads of both must maintain overall stability and if the settlement of foundation produce in building scope permitted inside, and foundation itself should have sufficient strength, stiffness and durability, also consider repair methods and the necessary foundation soil retaining retaining water and relevant measures. [3]As people living standard rise ceaselessly, the people to their place of building space has become not only from the number, and put forward higher requirement from quality are put car higher demands that the environment is beautiful, have certain comfort. This needs to decorate a building to be necessary. If architecture major engineering constitutes the skeleton of the building, then after adornment building has become the flesh-and-blood organism, final with rich, perfect appearance in people's in front, the best architecture should fully embody all sorts of adornment material related properties, with existing construction technology, the most effective gimmick, to achieve conception must express effect. Building outfit fix to consider the architectural space use requirement, protect the subject institutions from damage, give a person with beautifulenjoying, satisfy the requirements of fire evacuation, decorative materials and scheme of rationality, construction technology and economic feasibility, etc. Housing construction development and at the same time, like housing construction as affecting people life of roads, Bridges, tunnels has made great progress.In general civil engineering is one of the oldest subjects, it has made great achievements, the future of the civil engineering will occupy in people's life more important position. The environment worsening population increase, people to fight for survival, to strive for a more comfortable living environment, and will pay more attention to civil engineering. In the near future, some major projects extimated to build, insert roller skyscrapers, across the oceanBridges, more convenient traffic would not dream. The development of science and technology, and the earth is deteriorating environment will be prompted civil engineering to aerospace and Marine development, provide mankind broader space of living. In recent years, engineering materials mainly is reinforced concrete, lumber and brick materials, in the future, the traditional materials will be improved, more suitable for some new building materials market, especially the chemistry materials will promote the construction of towards a higher point. Meanwhile, design method of precision, design work of automation, information and intelligent technology of introducing, will be people have a morecomfortable living environment. The word, and the development of the theory and new materials, the emergence of the application of computer, high-tech introduction to wait to will make civil engineering have a new leap.This is a door needs calm and a great deal of patience and attentive professional. Because hundreds of thousands, even hundreds of thousands of lines to building each place structure clearly reflected. Without a gentle state of mind, do what thing just floating on the surface, to any a building structure, to be engaged in business and could not have had a clear, accurate and profound understanding of, the nature is no good. In this business, probably not burn the midnight oil of courage, not to reach the goal of spirit not to give up, will only be companies eliminated.This is a responsible and caring industry. Should have a single responsible heart - I one's life in my hand, thousands of life in my hand. Since the civil, should choose dependably shoulder the responsibility.Finally, this is a constant pursuit of perfect industry. Pyramid, spectacular now: The Great Wall, the majestic... But if no generations of the pursuit of today, we may also use the sort of the oldest way to build this same architecture. Design a building structure is numerous, but this is all experienced centuries of clarification, through continuous accumulation, keep improving, innovation obtained. And such pursuit, not confined in the past. Just think, if the design of a building can be like calculation one plus one equals two as simple and easy to grasp, that was not for what? Therefore, a civil engineer is in constant of in formation. One of the most simple structure, the least cost, the biggest function. Choose civil, choosing a steadfast diligence, innovation, pursuit of perfect path.Reference:[1] LuoFuWu editor. Civil engineering (professional). Introduction to wuhan. Wuhan university of technology press. 2007[2] WangFuChuan, palace rice expensive editor. Construction engineering materials. Beijing. Science and technology literature press. 2002[3] jiang see whales, zhiming editor. Civil engineering introduction of higher education press. Beijing.. 1992土木工程概论 [译文]摘要：土木工程是个庞大的学科，但最主要的是建筑，建筑无论是在中国还是在国外，都有着悠久的历史，长期的发展历程。
土木工程-毕业设计-论文-外文翻译-中英文对照
英文原文：Concrete structure reinforcement designSheyanb oⅠWangchenji aⅡⅠFoundation Engineering Co., Ltd. Heilongjiang DongyuⅡHeilongjiang Province, East Building Foundation Engineering Co., Ltd. CoalAbstract：structure in the long-term natural environment and under the use environment's function, its function is weaken inevitably gradually, our structural engineering's duty not just must finish the building earlier period the project work, but must be able the science appraisal structure damage objective law and the degree, and adopts the effective method guarantee structure the security use, that the structure reinforcement will become an important work. What may foresee will be the 21st century, the human building also by the concrete structure, the steel structure, the bricking-up structure and so on primarily, the present stage I will think us in the structure reinforcement this aspect research should also take this as the main breakthrough direction.Key word：Concrete structure reinforcement bricking-up structure reinforcement steel structure reinforcement1 Concrete structure reinforcementConcrete structure's reinforcement divides into the direct reinforcement and reinforces two kinds indirectly, when the design may act according to the actual condition and the operation requirements choice being suitable method and the necessary technology.1.1the direct reinforcement's general method1）Enlarges the section reinforcement lawAdds the concretes cast-in-place level in the reinforced concrete member in bending compression zone, may increase the section effective height, the expansion cross sectional area, thus enhances the component right section anti-curved, the oblique section anti-cuts ability and the section rigidity, plays the reinforcement reinforcement the role.In the suitable muscle scope, the concretes change curved the component right section supporting capacity increase along with the area of reinforcement and the intensity enhance. In the original component right section ratio of reinforcement not too high situation, increases the main reinforcement area to be possible to propose the plateau component right section anti-curved supporting capacity effectively. Is pulled in the section the area to add the cast-in-place concrete jacket to increase the component section, through new Canada partial and original component joint work, but enhances the component supporting capacity effectively, improvement normal operational performance.Enlarges the section reinforcement law construction craft simply, compatible, and has the mature design and the construction experience; Is suitable in Liang, the board, the column, the wall and the general structure concretes reinforcement; But scene construction's wet operating time is long, to produces has certain influence with the life, and after reinforcing the building clearance has certain reduction.2) Replacement concretes reinforcement lawThis law's merit with enlarges the method of sections to be close, and after reinforcing, does not affect building's clearance, but similar existence construction wet operating time long shortcoming; Is suitable somewhat low or has concretes carrier's and so on serious defect Liang, column in the compression zone concretes intensity reinforcement.3) the caking outsourcing section reinforcement lawOutside the Baotou Steel Factory reinforcement is wraps in the section or the steel plate is reinforced component's outside, outside the Baotou Steel Factory reinforces reinforced concrete Liang to use the wet outsourcing law generally, namely uses the epoxy resinification to be in the milk and so on methods with to reinforce the section the construction commission to cake a whole, after the reinforcement component, because is pulled with the compressed steel cross sectional area large scale enhancement, therefore right section supporting capacity and section rigidity large scale enhancement.This law also said that the wet outside Baotou Steel Factory reinforcement law, the stress is reliable, the construction is simple, the scene work load is small, but is big with the steel quantity, and uses in above not suitably 600C in the non-protection's situation the high temperature place; Is suitable does not allow in the use obviously to increase the original component section size, but requests to sharpen its bearing capacity large scale the concrete structure reinforcement.4) Sticks the steel reinforcement lawOutside the reinforced concrete member in bending sticks the steel reinforcement is (right section is pulled in the component supporting capacity insufficient sector area, right section compression zone or oblique section) the superficial glue steel plate, like this may enhance is reinforced component's supporting capacity, and constructs conveniently.This law construction is fast, the scene not wet work or only has the plastering and so on few wet works, to produces is small with the life influence, and after reinforcing, is not remarkable to the original structure outward appearance and the original clearance affects, but the reinforcement effect is decided to a great extent by the gummy craft and the operational level; Is suitable in the withstanding static function, and is in the normal humidity environment to bend or the tension member reinforcement.5) Glue fibre reinforcement plastic reinforcement lawOutside pastes the textile fiber reinforcement is pastes with the cementing material the fibre reinforcement compound materials in is reinforced the component to pull the region, causes it with to reinforce the section joint work, achieves sharpens the component bearing capacity the goal. Besides has glues the steel plate similar merit, but also has anticorrosive muddy, bears moistly, does not increase the self-weight of structure nearly, durably, the maintenance cost low status merit, but needs special fire protection processing, is suitable in each kind of stress nature concrete structure component and the general construction.This law's good and bad points with enlarge the method of sections to be close; Is suitable reinforcement which is insufficient in the concrete structure component oblique section supporting capacity, or must exert the crosswise binding force to the compressional member the situation.6) Reeling lawThis law's good and bad points with enlarge the method of sections to be close; Is suitable reinforcement which is insufficient in the concrete structure component oblique section supporting capacity, or must exert the crosswise binding force to the compressional member the situation.7) Fang bolt anchor lawThis law is suitable in the concretes intensity rank is the C20~C60 concretes load-bearing member transformation, the reinforcement; It is not suitable for already the above structure which and the light quality structure makes decent seriously. 1.2The indirect reinforcement's general method1)Pre-stressed reinforcement law(1)Thepre-stressed horizontal tension bar reinforces concretes member in bending,because the pre-stressed and increases the exterior load the combined action, in the tension bar has the axial tension, this strength eccentric transmits on the component through the pole end anchor (, when tension bar and Liang board bottom surface close fitting, tension bar can look for tune together with component, this fashion has partial pressures to transmit directly for component bottom surface), has the eccentric compression function in the component, this function has overcome the bending moment which outside the part the load produces, reduced outside the load effect, thus sharpened component's anti-curved ability. At the same time, because the tension bar passes to component's pressure function, the component crack development can alleviate, the control, the oblique section anti-to cut the supporting capacity also along with it enhancement.As a result of the horizontal lifting stem's function, the original component's section stress characteristic by received bends turned the eccentric compression, therefore, after the reinforcement, component's supporting capacity was mainly decided in bends under the condition the original component's supporting capacity 。
土木工程外文文献翻译(含中英文)
Experimental research on seismic behavior of abnormal jointin reinforced concrete frameAbstract :Based on nine plane abnormal joint s , one space abnormal joint experiment and a p seudo dynamic test of a powerplant model , the work mechanism and the hysteretic characteristic of abnormal joint are put to analysis in this paper. A conception of minor core determined by the small beam and small column , and a conclusion that the shear capacity of ab2normal joint depends on minor core are put forward in this paper. This paper also analyzes the effect s of axial compres2 sion , horizontal stirrup s and section variation of beam and column on the shear behavior of abnormal joint . Finally , the formula of shear capacity for abnormal joint in reinforced concrete f rame is provided.Key words : abnormal j oint ; minor core ; seismic behavior ; shear ca paci t yCLC number :TU375. 4 ; TU317. 1 Document code :A Article ID :100627930 (2006) 022*******1 Int roductionFor reinforced concrete f rame st ructure , t he joint is a key component . It is subjected to axialcomp ression , bending moment and shear force. The key is whet her the joint has enough shear capaci2ty. The Chinese Code f or S eismic Desi gn of B ui l di ngs ( GB5001122001) adopt s the following formulato calculate t he shear capacity of the reinforced concrete f rame joint .V j = 1. 1ηj f t b j h j + 0. 05ηj Nb jb c+ f yv A svjh b0 - a′ss(1)Where V j = design value of t he seismic shear capacity of the joint core section ;ηj = influential coefficient of t he orthogonal beam to the column ;f t = design value of concrete tensile st rength ;b j = effective widt h of the joint core section ;h j = dept h of the joint core section , Which can be adopted as t he depth of the column section int he verification direction ;N = design value of axial compression at t he bot tom of upper column wit h considering the combi2 nation of the eart hquake action , When N > 015 f c b c h c , let N = 0. 5 f c b c h c ;b c = widt h of t he column section ;f yv = design value of t he stirrup tensile st rengt h ;A svj = total stirrup area in a set making up one layer ;h b0 = effective dept h of t he beam.If t he dept h of two beams at the side of t he joint is unequal , h b0 = t he average depth of two beams.a′s = distance f rom the cent roid of the compression beam steel bar to the ext reme concrete fiber . s = distance of t he stirrup .Eq. 1 is based on t he formula in t he previous seismiccode[1 ] and some modifications made eavlicr and it is suit2able to the normal joint of reinforced concrete f rame , butnot to t he abnormal one which has large different in t hesection of t he upper column and lower one (3 600 mm and1 200 mm) , lef t beam and right beam (1 800 mm and 1200 mm) . The shear capacity of abnormal joint s calculat2ed by Eq. 1 may cause some unsafe result s. A type of ab2normal joint which of ten exist s in t he power plant st ruc2t ure is discussed ( see Fig. 1) , and it s behavior was st ud2ied based on t he experiment in t his paper2 Experimental workAccording to the above problem , and t he experiment of plane abnormal joint s and space abnormal joint , a p seudo dynamic test of space model of power plant st ruct ure was carried out . The aim of t hisst udy is to set up a shear force formula and to discuss seismic behavior s of t he joint s.According to the characteristic of t he power plant st ruct ure , nine abnormal joint s and one space abnormal joint were designed in t he experiment . The scale of the model s is one2fif t h. Tab. 1 and Tab.2 show t he dimensions and reinforcement detail s of t he specimens.Fig. 2 shows the typical const ruction drawing of t he specimen. Fig. 3 shows the loading set up . These specimens are subjected to low2cyclic loading , the loading process of which is cont rolled by force and displacement , t he preceding yield loading by force and subsequent yield by t he displacement .The shear deformation of the joint core , t he st rain of the longit udinal steel and t he stirrup are main measuring items.3 Analysis of test result s3. 1 Main resultsTab. 3 shows t he main result s of t he experiment .3. 2 Failure process of specimenBased on t he experiment , t he process of t he specimens’failure includes four stages , namely , t he initial cracking , t he t horough cracking , the ultimate stage and t he failure stage.(1) Initial cracking stageWhen t he first diagonal crack appears along t he diagonal direction in t he core af ter loading , it s widt h is about 0. 1mm , which is named initial cracking stage of joint core. Before t he initial cracking stage , t he joint remains elastic performance , and the variety of stiff ness is not very obvious on t hep2Δcurve. At t his stage concrete bear s most of the core shear force while stirrup bears few. At t he timewhen t he initial crack occur s , t he st ress of t he stirrup at t he crack increase sharply and t he st rain is a2bout 200 ×10 - 6 —300 ×10 - 6 . The shear deformation of t he core at t his stage is very small (less than 1×10 - 3 radian ,generally between 0. 4 ×10 - 3 and 0. 8 ×10 - 3 radian) .(2) Thorough cracking stageWit h the load increasing following t he initial cracking stage , the second and t hird crossing diago2 nal cracks will appear at t he core. The core is cut into some small rhombus pieces which will become at least one main inclined crack across t he core diagonal . The widt h of cracks enlarges obviously , andt he wider ones are generally about 0. 5mm , which is named core t horough cracking stage. The st ress of stirrup increases obviously , and the stirrup in t he middle of t he core is near to yielding or has yiel2 ded. The joint core shows nonlinear property on t he p2Δcurve , and it enter s elastic2plastic stage. Theload at t horough cracking stage is about 80 % —90 % load.(3) Ultimate stageAt t his stage , t he widt h of t he cracks is about 1mm or more and some new cracks continue to oc2 cur . The shear deformation at t he core is much larger and concrete begins to collap se. Af ter several cyclic loading , the force reaches the maximum value , which is called ultimate stage. The load increase is due to t he enhancing of the concrete aggregate mechanical f riction between cracks. At t he same timet he st ress of stirrup increases gradually. On t he one hand stirrup resist s t he horizontal shear , and on t he ot her hand the confinement effect to t he expanding compression concrete st rengthens continuous2ly , which can also improve t he shear capacity of diagonal compression bar mechanism.(4) Failure stageAs the load circulated , concrete in t he core began to collap se , and t he deformation increased sharply , while the capacity began to drop . It was found t hat t he slip of reinforcement in t he beam wasvery serious in t he experiment . Wit h t he load and it s circulation time increasing , t he zoon wit houtbond gradually permeated towards t he internal core , enhancing t he burden of t he diagonal compressionbar mechanism and accelerates the compression failure of concrete. Fig. 4 shows t he p hotos of typical damaged joint s.A p seudo dynamic test of space model ofpower plant st ruct ure was carried out to researcht he working behavior of t he abnormal joint s in re2al st ructure and the seismic behavior of st ructure.Fig. 5 shows the p hoto of model .The test includes two step s. The fir st is thep seudo dynamic test . At t his step , El2Cent rowave is inp ut and the peak acceleration variesf rom 50 gal to 1 200 gal . The seismic response is measured. The second is t he p seudo static test . Theloading can’t stop until t he model fail s.Fig. 7 Minor coreThe experiment shows t hat t he dist ribution and development of t hecrack is influenced by t he rest rictive effect of the ort hogonal beam , andt he crack of joint core mainly dist ributes under t he orthogonal beam( see Fig. 6) , which is different f rom t he result of t he plane joint test ,but similar to J 4210.3. 3 Analysis of test results3. 3. 1 Mechanical analysisIn t he experiment , t he location of the initial crack of t he exteriorjoint and the crushed position of concrete both appear in the middle oft he joint core , and t he position is near t he centerline of t he upper col2umn. The initial crack and crushed position of t he concrete of the interior joint both appear in t he mi2 nor core ( see Fig. 4 ,Fig. 7) . For interior abnormal joint t he crack doesn’t appear or develop in t he ma2j or core out side of the mi nor core until t horough cracking takes place , while t he crack seldom appearsin t he shadow region ( see Fig. 7) as the joint fail s. Therefore , for abnormal joint , t he shear capacity oft he joint core depends on t he properties of t he mi nor core , namely , on t he st rengt h grades of concrete ,t he size and the reinforcement of t he mi nor core , get t he effect of t he maj or core dimension can’t be neglected.Mechanical effect s are t he same will that of t he normal joint , when t he forces t ransfer to t he mi2 nor core t hrough column and beam and reinforcement bar . Therefore , t he working mechanisms of nor2mal joint , including t russ mechanism , diagonal compression bar mechanism and rest rictive mechanismof stirrup , are also suitable for mi nor core of t he abnormal joint , but their working characteristic is not symmet rical when the load rever ses. Fig. 8 illust rates t he working mechanism of t he abnormal joint .When t he load t ransfer to mi nor core , t he diagonal compression bar area of mi nor core is biggert han normal joint core2composed by small column and small beam of abnormal joint , which is due to t he compressive st ress diff usion of concrete compressive region of the beam and column , while at t hesame time t he compression carried by the diagonal compression bar becomes large. Because t he main part of bond force of column and beam is added to t he diagonal comp ression bar but cont rasting wit h t he increased area of diagonal compression bar , t he increased action is small . The region in the maj orcore but out of the mi nor core has less st ress dist ribution and fewer cracks. The region can confine t heexpansion of t he concrete of t he mi nor core diagonal compression bar concrete , which enhances t he concrete compressive st rengt h of mi nor core diagonal compression bar .Making t he mi nor core as st udy element , the area increment of concrete diagonal compression barin mi nor core is related to t he st ress diff usion of t he beam and column compressive region. The magni2t ude of diff usion area is related to height difference of t he beam sections and column sections. Name2ly , it is related to t he size of mi nor core section and maj or core section. Thus , the increased shearst rengt h magnit ude caused by mi nor core rest rictive effect on maj or core can be measured quantitative2ly by t he ratio of maj or core area to mi nor core area. And it al so can be expressed that t he rest rictive effect is quantitatively related to t he ratio. Obviously , t he bigger t he ratio is and t he st ronger t he con2finement is , t he st ronger t he bearing capacity is.The region in the maj or core but under the mi nor core still need stirrup bar because of t he hori2 zontal force t ransferred by bigger beam bar . But force is small .3. 3. 2 load2displacement curves analysisFig. 9 shows t he typical load2displacement curves at t he beam end of t he exterior and interiorjoint . The figure showing t hat t he rigidity of t he specimens almo st doesn’t degenerate when t he initialcrack appear s in t he core , and a turning point can be found at t he curve but it isn’t very obvious. Wit ht he crack developing , an obvious t urning point can be found at t he curve , and at t his time , t he speci2men yields. Then t he load can increase f urt her , but it can’t increase too much f rom yielding load to ultimate load. When t he concrete at t he core collap ses and the plastic hinge occured at t he beamend ,t he load begins to decrease rat her t han increase.The ductility coefficient of two kinds of joint s is basically more than 3 (except for J 3 - 9) . But it should be noted t hat the design of specimens is based on the principle of joint core failure. The ratio of reinforcement of beam and column tends to be lower t han practical project s. If t he ratio is larger , t he failure of joint is probably prior to t hat of beam and column , so t he hysteretic curve reflect s t he ductil ity property of joint core.Joint experiment should be a subst ruct ure test (or a test of composite body of beams and col2 umns) . So t he load2displacement curves at t he beam end should be a general reflection of t he joint be2havior work as a subst ruct ure. Providing t hat the joint core fails af ter t he yield of beam and column (especially for beam) , t he load2displacement curves at t he beam end is plump , so the principle of “st rong col umn and weak beam , st ron ger j oi nt" should be ensured which conforms to t he seismic re2sistant principle.The experiment shows t hat t he stiff ness of joint core is large. Before the joint reaches ultimatestage , t he stiff ness of joint core decreases a little and the irrecoverable residual deformation is very small under alternate loading. When joint core enter s failure stage , t he shear deformation increases sharply , and t he stiff ness of joint core decreases obviously , and t he hysteretic curve appears shrink2 age , which is because of t he cohesive slip of beam reinforcement .3. 4 Influential Factors of Abnormal Joint Shear CapacityThe fir st factor is axial compression. Axial compression can enlarge t he compression area of col2 umn , and increase t he concrete compression area of joint core[124 ] . At t he same time , more shearst ransferred f rom beam steel to t he edge of joint core concrete will add to t he diagonal compression bar ,which decreases t he edge shear t hat leads to the crack of joint core concrete. So t he existence of axial comp ression cont ributes to imp roving t he capacity of initial cracks at joint core.The effect of axial compression on t horough cracking load and ultimate load isn’t very obvious[1 ] . The reason is t hat cont rasting wit h no axial compression , the accumulated damage effect of joint coreunder rever sed loading wit h axial compression is larger . Alt hough axial compression can improve t heshear st rengt h of concrete , it increases accumulated damage effect which leads to a decrease of the ad2vantage of axial compression. Therefore t he effect of axial compression on t horough cracking loadandultimate load is not very obvious.Hence , considering the lack of test data of abnormal joint , t he shear capacity formula of abnormal joint adopt 0. 05 nf c b j h j to calculate the effect of axial compression , which is based on the result s of t his experiment and referenced to t he experimental st udy and statistical analysis of Meinheit and J irsa ,et [5 ] .The second factor is horizontal stirrup . Horizontal stirrup has no effect on t he initial crackingshear of abnormal joint , while greatly improves t he t horough cracking shear . Af ter crack appeared , t he stirrup begins to resist t he shear and confines t he expansion of concrete[ 6 ] . This experiment showst hat t he st ress of stirrup s in each layer is not equal . When the joint fail s , t he stirrup s don’t yield simultaneous. Fig. 10 shows t he change of st ress dist ribution of stirrup s along core height wit h t he loadincreasing. Through analyzing test result s , it can be known t hat 80 percent of the height at the joint core can yield.The last factor is the change of sec2tion size of t he beam and column. Thesection change decreases t he initial crack2ing load about 30 p resent of abnormaljoint and makes t he initial crack appear att he position of joint mi nor core. The rea2son for t his p henomenon is t hat small up2per column section makes t he confinementof mi nor core concrete decrease and t heedge shear increase. But t he section change has lit tle effect on thorough cracking load. Af ter t horoughcracking , the joint enter s ultimate state while the external load can’t increase too much , which is dif2 ferent f rom t he behavior of abnormal joint t hat can carry much shear af ter thorough cracking.3. 5 Shear force formula of abnormal jointAs a part of f rame , t he design of joint shall meet t he requirement s of the f rame st ruct ure design , namely , t he joint design should not damage t he basic performance of t he st ruct ure.According to the principle of st ronger j oi nt , it is necessary for joint to have some safety reserva2 tion. The raised cost for conservational estimation of t he joint bearing capacity is small . But t he con2 servational estimation is very important to t he safety of the f rame st ruct ure. At t horough cracking stage , t he widt h of most cracks is more t han 0. 2 mm , which is bigger than t he suggested limit value in t he concrete design code. Big cracks will influence t he durability of st ruct ure. Hence , the bearing capacity at t horough cracking stage is applied to calculating t he bearing capacity of joint . According to t he analysis of t he working mechanisms of abnormal joint , it could be concludedt hat t he bearing capacity of joint core mainly depends on mi nor core when t he force t ransferred f rommaj or core to mi nor core. All kinds of working mechanisms are suitable to mi nor core element . Thus , a formula for calculating t he shear capacity of abnormal joint can be obtained based on Eq. 1. According to the above analysis of influential factor s of shear capacity of abnormal joint , and ref2 erence to Eq. 1 , a formula for calculating t he shear capacity of reinforced concrete f rame abnormal jointis suggested as followsV j = 0. 1ηjξ1 f c b j h j + 0. 1ηj nξ2 f c b j h j +ξ3 f yv A svj h0 - a′s s(2)Where h0 = effective dept h of small beam section in abnormal joint ;ξ1 = influential coefficient consider2ing mi nor core on working as cont rol element for calculating ;ξ2 = influential coefficient considering effect of axial compression ratio , it s value is 0. 5 , andξ3 = influential coefficient considering t hestir2rup doesn’t yield simultaneous , it s value is 0. 8 , n = N/ f c b c h j .From Fig. 8 , the shear capacity of abnormal joint depends on mi nor core , while maj or core has re2st rictive effect on mi nor core. The effect is related to t he ratio of maj or core area to mi nor core area , so assumingξ1 =αA d A x (3)Where A d = area of abnormal joint maj or core , choosing it as t he value of t he dept h of big beam multiplying t he height of lower column ; A x = area of abnormal joint mi nor core , choosing it as t he value oft he depth of small beam multiplying the height of upper column ; andα= parameter to be defined , it s value is 0. 8 derived f rom t he result s of t he experiment ( see Tab. 4)Then Eq. 2 can be replaced byV j = 0. 1ηjαA d A x f c b j h j + 0. 05ηj n f c b j h j + 0. 8 f yv h0 - a′s s(4)4 ConclusionsThe following conclusions can be drawn f rom t his study.(1) The seismic behavior of abnormal joint in reinforced concrete f rame st ruct ure is poor . Af tert horough cracking , t he joint enter s ultimate state while the external load can’t increase too much , andt he safety reservation of joint isn’t sufficient .(2) The characteristic of bearing load of minor core is similar to that of normal joint , but t he area bearing load is different . The shear capacity depend on t he size , t he st rengt h of concrete and the rein2forcement of mi nor core in abnormal joint . The maj or core has rest rictive effect on mi nor core. (3) Joint experiment should be a subst ruct ure test or a test of composite body of beams and col2 umns. Therefore t he load2displacement curves of t he beam end should be a general reflection of t he joint behavior working as a subst ruct ure. Studies of t he hysteretic curve of subst ruct ure should be based on t he whole st ructure. It is critical to guarantee t he stiff ness and st rengt h of joint core in prac2tice.(4) The formula of shear capacity for abnormal joint in reinforced concrete f rame is provided.References[1 ] TAN GJ iu2ru . The seismic behavior of steel reinforced concrete f rame [M] . Nanjing :Dongnan University Press ,1989 :1572163.[2 ] The research group of reinforcement concrete f rame joint . Shear capacity research of reinforced concrete f rame jointon reversed2cyclic loading[J ] . Journal of Building St ructures , 1983 , (6) :9215.[3 ] PAULA Y T ,PARK R. Joint s reinforced concrete f rames designed for earthquake resistance[ R] . New Zealand :De2partment of civil Engineering , University of Canterbury , Christchurch , 1984.[4 ] FU Jian2ping. Seismic behavior research of reinforced concrete f rame joint with the consideration of axialforce[J ] .Journal of Chongqing Univ , 2000 , (5) :23227.[5 ] MEINHEIT D F ,J IRSA J O. Shear st rength of R/ C beam2column connections [J ] . ACI St ructural Journal , 1993 ,(3) :61271.[6 ] KITA YAMA K, OTANI S ,AO YAMA H. Development of design criteria for RC interior beam2column joints ,de2sign of beam2column joint s for seismic resistance[ R] . SP123 ,ACI ,Det roit , 1991 :61272.[7 ] GB5001122001 ,Code for seismic design of buildings [ S] . Beijing : China Architectural and BuildingPress ,2001.钢筋混凝土框架异型节点抗震性能试验研究摘要：基于8个钢筋混凝土框架异型节点的试验研究，分析了异型框架节点的受力与常规框架节点的异同。
土木工程类专业英文文献及翻译
土木工程类专业英文文献及翻译第一篇：土木工程类专业英文文献及翻译PAVEMENT PROBLEMS CAUSEDBY COLLAPSIBLE SUBGRADESBy Sandra L.Houston,1 Associate Member, ASCE(Reviewed by the Highway Division)ABSTRACT: Problem subgrade materials consisting of collapsible soils are com-mon in arid environments, which have climatic conditions and depositional and weathering processes favorable to their formation.Included herein is a discussion of predictive techniques that use commonly available laboratory equipment and testing methods for obtaining reliable estimates of the volume change for these problem soils.A method for predicting relevant stresses and corresponding collapse strains for typical pavement subgrades is presented.Relatively simple methods of evaluating potential volume change, based on results of familiar laboratory tests, are used.INTRODUCTION When a soil is given free access to water, it may decrease in volume,increase in volume, or do nothing.A soil that increases in volume is called a swelling or expansive soil, and a soil that decreases in volume is called a collapsible soil.The amount of volume change that occurs depends on the soil type and structure, the initial soil density, the imposed stress state, and the degree and extent of wetting.Subgrade materials comprised of soils that change volume upon wetting have caused distress to highways since the be-ginning of the professional practice and have cost many millions of dollars in roadway repairs.The prediction of the volume changes that may occur in the field is the first step in making an economic decision for dealing withthese problem subgrade materials.Each project will have different design considerations, economic con-straints, and risk factors that will have to be taken into account.However, with a reliable method for making volume change predictions, the best design relative to the subgrade soils becomes a matter of economic comparison, and a much more rational design approach may be made.For example, typical techniques for dealing with expansive clays include:(1)In situ treatments with substances such as lime, cement, or fly-ash;(2)seepage barriers and/ or drainage systems;or(3)a computing of the serviceability loss and a mod-ification of the design to “accept” the anticipated expansion.In order to make the most economical decision, the amount of volume change(especially non-uniform volume change)must be accurately estimated, and the degree of road roughness evaluated from these data.Similarly, alternative design techniques are available for any roadway problem.The emphasis here will be placed on presenting economical and simple methods for:(1)Determining whether the subgrade materials are collapsible;and(2)estimating the amount of volume change that is likely to occur in the 'Asst.Prof., Ctr.for Advanced Res.in Transp., Arizona State Univ., Tempe, AZ 85287.Note.Discussion open until April 1, 1989.To extend the closing date one month,a written request must be filed with the ASCE Manager of Journals.The manuscriptfor this paper was submitted for review and possible publication on February 3, 1988.This paper is part of the Journal of Transportation.Engineering, Vol.114, No.6,November, 1988.ASCE, ISSN 0733-947X/88/0006-0673/$1.00 + $.15 per page.Paper No.22902.673field for the collapsible soils.Then this information will place the engineerin a position to make a rational design decision.Collapsible soils are fre-quently encountered in an arid climate.The depositional process and for-mation of these soils, and methods for identification and evaluation of theamount of volume change that may occur, will be discussed in the followingsections.COLLAPSIBLE SOILSFormation of Collapsible SoilsCollapsible soils have high void ratios and low densities and are typicallycohesionless or only slightly cohesive.In an arid climate, evaporation greatlyexceeds rainfall.Consequently, only the near-surface soils become wettedfrom normal rainfall.It is the combination of the depositional process andthe climate conditions that leads to the formation of the collapsible soil.Although collapsible soils exist in nondesert regions, the dry environment inwhich evaporation exceeds precipitation is very favorable for the formationof the collapsible structure.As the soil dries by evaporation, capillary tension causes the remainingwater to withdraw into the soil grain interfaces, bringing with it soluble salts,clay, and silt particles.As the soil continues to dry, these salts, clays, andsilts come out of solution, and “tack-we ld” the larger grains together.Thisleads to a soil structure that has high apparent strength at its low, naturalwater content.However, collapse of the “cemented” structure may occurupon wetting because the bonding material weakens and softens, and the soilis unstable at any stress level that exceeds that at which the soil had beenpreviously wetted.Thus, if the amount of water made available to the soilis increased above that which naturally exists, collapse can occur at fairlylow levels of stress, equivalent only to overburden soil pressure.Additionalloads, such as traffic loading or the presence of a bridge structure, add tothe collapse, especially of shallow collapsible soil.The triggering mechanismfor collapse, however, is the addition of water.Highway Problems Resulting from Collapsible SoilsNonuniform collapse can result from either a nonhomogeneous subgradedeposit in which differing degrees of collapse potential exist and/or fromnonuniform wetting of subgrade materials.When differential collapse ofsubgrade soils occurs, the result is a rough, wavy surface, and potentiallymany miles of extensively damaged highway.There have been several re-ported cases for which differential collapse has been cited as the cause ofroadway or highway bridge distress.A few of these in the Arizona and NewMexico region include sections of 1-10 near Benson, Arizona, and sectionsof 1-25 in the vicinity of Algadonas, New Mexico(Lovelace et al.1982;Russman 1987).In addition to the excessive waviness of the roadway sur-face, bridge foundations failures, such as the Steins Pass Highway bridge,1-10, in Arizona, have frequently been identified with collapse of foundationsoils.Identification of Collapsible SoilsThere have been many techniques proposed for identifying a collapsiblesoil problem.These methods range from qualitative index tests conducted on4disturbed samples, to response to wetting tests conducted on relatively un-disturbed samples, to in situ meausrement techniques.In all cases, the en-gineer must first know if the soils may become wetted to a water contentabove their natural moisture state, and if so, what the extent of the potentialwetted zone will be.Most methods for identifying collapsible soils are onlyqualitative in nature, providing no information on the magnitude of the col-lapse strain potential.These qualitative methods are based on various func-tions of dry density, moisture content, void ratio, specific gravity, and At-terberg limits.In situ measurement methods appear promising in some cases, in that manyresearchers feel that sample disturbance is greatly reduced, and that a morenearly quantitative measure of collapse potential is obtainable.However,in situ test methods for collapsible soils typically suffer from the deficien-cy of an unknown extent and degree of wetting during the field test.Thismakes a quantitative measurement difficult because the zone of materialbeing influenced is not well-known, and, therefore, the actual strains, in-duced by the addition of stress and water, are not well-known.In addition,the degree of saturation achieved in the field test is variable and usuallyunknown.Based on recently conducted research, it appears that the most reliablemethod for identifying a collapsible soil problem is to obtain the best qualityundisturbed sample possible and to subject this sample to a response to wet-ting test in the laboratory.The results of a simple oedometer test will indicatewhether the soil is collapsible and, at the same time, give a direct measureof the amount of collapse strain potential that may occur in the field.Potentialproblems associated with the direct sampling method include sample distur-bance and the possibility that the degree of saturation achieved in the fieldwill be less than that achieved in the laboratory test.The quality of an undisturbed sample is related most strongly to the arearatio of the tube that is used for sample collection.The area ratio is a measureof the ratio of the cross-sectional area of the sample collected to the cross-sectional area of the sample tube.A thin-walled tube sampler by definitionhas an area ratio of about 10-15%.Although undisturbed samples are bestobtained through the use of thin-walled tube samplers, it frequently occursthat these stiff, cemented collapsible soils, especially those containing gravel,cannot be sampled unless a tube with a much thicker wall is used.Samplershaving an area ratio as great as 56% are commonly used for Arizona col-lapsible soils.Further, it may take considerable hammering of the tube todrive the sample.The result is, of course, some degree of sample distur-bance, broken.bonds, densification, and a correspondingly reduced collapsemeasured upon laboratory testing.However, for collapsible soils, which arecompressive by definition, the insertion of the sample tube leads to localshear failure at the base of the cutting edge, and, therefore, there is lesssample disturbance than would be expected for soils that exhibit general shearfailure(i.e., saturated clays or dilative soils).Results of an ongoing studyof sample disturbance for collapsible soils indicate that block samples some-times exhibit somewhat higher collapse strains compared to thick-walled tubesamples.Block samples are usually assumed to be the very best obtainableundisturbed samples, although they are frequently difficult-to-impossible toobtain, especially at substantial depths.The overall effect of sample distur-bance is a slight underestimate of the collapse potential for the soil.675译文：湿陷性地基引起的路面问题作者：...摘要：在干旱环境中，湿陷性土壤组成的路基材料是很常见的，干旱环境中的气候条件、沉积以及风化作用都有利于湿陷性土的形成。
土木工程毕业论文英文翻译
BridgeBridges that span rivers, valleys such a barrier construction, which provides convenient transportation, so far, most of the bridges are highway bridges or railway bridge. A large number of viaducts built in the 19th century in Europe, aims to maintain its navigation of the ship canal. The smallest bridge in New York City's Kennedy Airport, it is primarily the aircraft taxiing onto the runway to the service.Humans is similar to the first bridge built in the primitive built in isolated areas. Early human tools and construction techniques as the original, like humans are the most junior. After they are at least as long as the processing and installation can be completed.In the forest, widely available solid wood and logs, then most likely Hou bridge or by a few logs built side by side, may, in its number of wooden sticks or straw mats on the cover for easy walking.In the tropical regions of India, Africa, and South America are used to build fiber rattan suspension bridge, the vines are tied to trees on both sides of the river or valley or rock.One or more above the walking cane to be stepped on, others are arranged in Gao Yu a few feet, for hand use. Although rattan rope bridge is usually unstable. But there are many rattan rope bridge with incas built strong and stable enough, to be used for the Spanish soldiers and their horses to pass.In rocky areas, the stone is used to bridge across the river to a small stone pestle as piers spaced, and then use a flat stone across the pier adjacent to the channel linking the two sides completed, most of the stone bridge is this types, called the clap bridge. Now in Dartmoor, England are still visible, but they are built in the Middle Ages or even later.The first step changes the original bridge was considered in ancient China, and then into India. Generally wider than the tree bed, Chinese and Indians in the center of the river into two stumps. In this structure, both ends of the frame with one end of logs on the stump, and tilted slightly upward so that each layer of high than a few feet below it. In order to increase stability, both sides each with a bunch of stakes in large and heavy stone anchor; close to the river, in the middle of the river at both ends of the two stakes are connected with beams.In this structure, the natural bridge support bar in the middle of two free pile after a wide span can be achieved.As early as 4000 BC in Mesopotamia, and thousands in the year 3000 in Egypt, with stone or sun dried bricks were used to install the overlapping beams. This structure looks like the arch, the lower more stable, is called sudden arch. To suddenly arch into a more straight arch, it needs to fit the internal structure of the stone smooth. The arch straight arch stronger than sudden, and as early as 500 BC to be used.The stone arch with direct economic and durable, it can rest on the dock by a number of the arch and across the small river. And, it generally will always appear, and its quality in any structure to be better than the previous. In ancient China and Rome, which is widely used in the overall stone arch bridge structure. It has been widely used until the 19th century. There are four categories of basic structure can be used as water or obstructions on the bridge: rigid frame bridge, cantilever bridge, arch, and suspension system.The simplest bridge may be just the first use - or just the river bridge. So that it is relatively fixed at both ends ofthe banks. This rigid frame bridge can form a shaped wooden beams, reinforced concrete beams or more complicated constraints. Just this type of bridge span of the bridge pier was built in the middle can be used or built in the valley support joists, beams connected by a few and then increase the span. Rigid Frame material must be able to bear the stress and tension. Despite its name beam, but in fact the requirements of this dual rod can be used to frame the bridge. Result, the higher part of the beam bending pressure lower than the straight part of the more than half, if he's bearing strength is too weak, it will be into the ring, if the tensile capacity is too weak, he will be destroyed.Cantilever bridge piers in the use of long-span bridges the middle it is usually not feasible in the bridge structure. For example, in the deep and rapid river flow, or ooze, it may make it difficult to build sufficient depth of bridge pier foundation rock. In this case, just on the bridge structure can be extended with two beams --- out of a beam from each shore, and in the two ends of the beam anchorage basis. This simple structure is more rigid frame bridge with static characterization, and each root anchorage of the beam cantilever bridge called such an infrastructure, and perhapsthis most simple and familiar example is the cantilever bridge diving board. Cantilever bridge in general, the gap between the cantilever tip is closed, the road to provide a continuous deck. But if the point of this bridge in its closed off, then do not need each other to set the root cantilever support which can maintain stability. Cantilever is usually only the middle of the gap is closed rigid frame bridge. So while filling grain extended cantilever span.Suspension bridge in the absence than in the case of the middle pier cantilever bridge across the greater distance. Suspension of the support system is a continuous flexible cables by the ends of the anchor, the suspension bridge is the simplest example of high-altitude high-wire acrobat with the circus wire. The original suspension bridge is often a very small few that is tied to steel rails and provide a foothold. At the level of the modern suspension bridge on the road is suspended by the cable on both sides of the roadway below.Arch is the opposite effect on the suspension bridge, suspension bridge cables in the freedom of those who provide support force where it is from the bridge pillars at both ends of its fixed upward. As different in shape, suspension bridgecables tend to stretch all the points of the pillars of the bridge tends to squeeze everywhere. For these reasons, suspension of the cable must be as much as possible to prevent the extension of the bridge material is as hungry to resist compression. Because the arch does not necessarily require materials with a tensile strength, so the bridge can be built with brick or stone, brick or stone arch to pass through the characteristics of the pressure together. This material in other basic bridge structure is useless.In the arch, the load on the vertical transmission from the road down until the arch was destroyed. When the arch was pure pressure to achieve the critical load, they will change the power transmission path. A compression force of the thrust through the node or piers to the ground. This simple and beautiful arch structure of a bridge in one of the basic structure.桥梁桥梁是跨越如河流、山谷这样障碍的一种建筑，从而提供交通便利，到目前为止，大部分桥梁都是公路桥或铁路桥。
土木工程毕业论文中英文翻译
外文翻译班级：xxx学号：xxx姓名：xxx一、外文原文：Structural Systems to resist lateral loads Commonly Used structural SystemsWith loads measured in tens of thousands kips, there is little room in the design of high-rise buildings for excessively complex thoughts. Indeed, the better high-rise buildings carry the universal traits of simplicity of thought and clarity of expression.It does not follow that there is no room for grand thoughts. Indeed, it is with such grand thoughts that the new family of high-rise buildings has evolved. Perhaps more important, the new concepts of but a few years ago have become commonplace in today’ s technology.Omitting some concepts that are related strictly to the materials of construction, the most commonly used structural systems used in high-rise buildings can be categorized as follows:1.Moment-resisting frames.2.Braced frames, including eccentrically braced frames.3.Shear walls, including steel plate shear walls.4.Tube-in-tube structures.5.Core-interactive structures.6.Cellular or bundled-tube systems.Particularly with the recent trend toward more complex forms, but in response also to the need for increased stiffness to resist the forces from wind and earthquake, most high-rise buildings have structural systems built up of combinations of frames, braced bents, shear walls, and related systems. Further, for the taller buildings, the majorities are composed of interactive elements in three-dimensional arrays.The method of combining these elements is the very essence of the design process for high-rise buildings. These combinations need evolve in response to environmental, functional, and cost considerations so as to provide efficient structures that provoke the architectural development to new heights. This is not to say that imaginative structural design can create great architecture. To the contrary, many examples of fine architecture have been created with only moderate support from the structural engineer, while only fine structure, not great architecture, can be developed without the genius and the leadership of a talented architect. In any event, the best of both is needed to formulate a truly extraordinary design of a high-rise building.While comprehensive discussions of these seven systems are generally available in the literature, further discussion is warranted here .The essence of the design process is distributed throughout the discussion.Moment-Resisting FramesPerhaps the most commonly used system in low-to medium-rise buildings, the moment-resisting frame, is characterized by linear horizontal and vertical members connected essentially rigidly at their joints. Such frames are used as a stand-alone system or in combination with other systems so as to provide the needed resistance to horizontal loads. In the taller of high-rise buildings, the system is likely to be found inappropriate for a stand-alone system, this because of the difficulty in mobilizing sufficient stiffness under lateral forces.Analysis can be accomplished by STRESS, STRUDL, or a host of other appropriate computer programs; analysis by the so-called portal method of the cantilever method has no place in today’s technology.Because of the intrinsic flexibility of the column/girder intersection, and because preliminary designs should aim to highlight weaknesses of systems, it is not unusual to use center-to-center dimensions for the frame in the preliminary analysis. Of course, in the latter phases of design, a realistic appraisal in-joint deformation is essential.Braced Frame sThe braced frame, intrinsically stiffer than the moment –resisting frame, finds also greater application to higher-rise buildings. The system is characterized by linear horizontal, vertical, and diagonal members, connected simply or rigidly at their joints. It is used commonly inconjunction with other systems for taller buildings and as a stand-alone system in low-to medium-rise buildings.While the use of structural steel in braced frames is common, concrete frames are more likely to be of the larger-scale variety.Of special interest in areas of high seismicity is the use of the eccentric braced frame.Again, analysis can be by STRESS, STRUDL, or any one of a series of two –or three dimensional analysis computer programs. And again, center-to-center dimensions are used commonly in the preliminary analysis. Shear wallsThe shear wall is yet another step forward along a progression of ever-stiffer structural systems. The system is characterized by relatively thin, generally but not always concrete elements that provide both structural strength and separation between building functions.In high-rise buildings, shear wall systems tend to have a relatively high aspect ratio, that is, their height tends to be large compared to their width. Lacking tension in the foundation system, any structural element is limited in its ability to resist overturning moment by the width of the system and by the gravity load supported by the element. Limited to a narrow overturning, One obvious use of the system, which does have the needed width, is in the exterior walls of building, where the requirement for windows is kept small.Structural steel shear walls, generally stiffened against buckling by a concrete overlay, have found application where shear loads are high. The system, intrinsically more economical than steel bracing, is particularly effective in carrying shear loads down through the taller floors in the areas immediately above grade. The system has the further advantage of having high ductility a feature of particular importance in areas of high seismicity.The analysis of shear wall systems is made complex because of the inevitable presence of large openings through these walls. Preliminary analysis can be by truss-analogy, by the finite element method, or by making use of a proprietary computer program designed to consider the interaction, or coupling, of shear walls.Framed or Braced TubesThe concept of the framed or braced or braced tube erupted into the technology with the IBM Building in Pittsburgh, but was followed immediately with the twin 110-story towers of the World Trade Center, New York and a number of other buildings .The system is characterized by three –dimensional frames, braced frames, or shear walls, forming a closed surface more or less cylindrical in nature, but of nearly any plan configuration. Because those columns that resist lateral forces are placed as far as possible from the cancroids of the system, the overall moment of inertia is increased and stiffness is very high.The analysis of tubular structures is done using three-dimensional concepts, or by two- dimensional analogy, where possible, whichever method is used, it must be capable of accounting for the effects of shear lag.The presence of shear lag, detected first in aircraft structures, is a serious limitation in the stiffness of framed tubes. The concept has limited recent applications of framed tubes to the shear of 60 stories. Designers have developed various techniques for reducing the effects of shear lag, most noticeably the use of belt trusses. This system finds application in buildings perhaps 40stories and higher. However, except for possible aesthetic considerations, belt trusses interfere with nearly every building function associated with the outside wall; the trusses are placed often at mechanical floors, mush to the disapproval of the designers of the mechanical systems. Nevertheless, as a cost-effective structural system, the belt truss works well and will likely find continued approval from designers. Numerous studies have sought to optimize the location of these trusses, with the optimum location very dependent on the number of trusses provided. Experience would indicate, however, that the location of these trusses is provided by the optimization of mechanical systems and by aesthetic considerations, as the economics of the structural system is not highly sensitive to belt truss location.Tube-in-Tube StructuresThe tubular framing system mobilizes every column in the exterior wallin resisting over-turning and shearing forces. The term‘tube-in-tube’is largely self-explanatory in that a second ring of columns, the ring surrounding the central service core of the building, is used as an inner framed or braced tube. The purpose of the second tube is to increase resistance to over turning and to increase lateral stiffness. The tubes need not be of the same character; that is, one tube could be framed, while the other could be braced.In considering this system, is important to understand clearly the difference between the shear and the flexural components of deflection, the terms being taken from beam analogy. In a framed tube, the shear component of deflection is associated with the bending deformation of columns and girders , the webs of the framed tube while the flexural component is associated with the axial shortening and lengthening of columns , the flanges of the framed tube. In a braced tube, the shear component of deflection is associated with the axial deformation of diagonals while the flexural component of deflection is associated with the axial shortening and lengthening of columns.Following beam analogy, if plane surfaces remain plane , the floor slabs,then axial stresses in the columns of the outer tube, being farther form the neutral axis, will be substantially larger than the axial stresses in the inner tube. However, in the tube-in-tube design, when optimized, the axial stresses in the inner ring of columns may be as high, or evenhigher, than the axial stresses in the outer ring. This seeming anomaly is associated with differences in the shearing component of stiffness between the two systems. This is easiest to under-stand where the inner tube is conceived as a braced , shear-stiff tube while the outer tube is conceived as a framed , shear-flexible tube.Core Interactive StructuresCore interactive structures are a special case of a tube-in-tube wherein the two tubes are coupled together with some form of three-dimensional space frame. Indeed, the system is used often wherein the shear stiffness of the outer tube is zero. The United States Steel Building, Pittsburgh, illustrates the system very well. Here, the inner tube is a braced frame, the outer tube has no shear stiffness, and the two systems are coupled if they were considered as systems passing in a straight line from the “hat” structure. Note that the exterior columns would be improperly modeled if they were considered as systems passing in a straight line from the “hat” to the foundations; these columns are perhaps 15% stiffer as they follow the elastic curve of the braced core. Note also that the axial forces associated with the lateral forces in the inner columns change from tension to compression over the height of the tube, with the inflection point at about 5/8 of the height of the tube. The outer columns, of course, carry the same axial force under lateral load for the full height of the columns because the columns because the shearstiffness of the system is close to zero.The space structures of outrigger girders or trusses, that connect the inner tube to the outer tube, are located often at several levels in the building. The AT&T headquarters is an example of an astonishing array of interactive elements:1.The structural system is 94 ft wide, 196ft long, and 601ft high.2.Two inner tubes are provided, each 31ft by 40 ft , centered 90 ft apartin the long direction of the building.3.The inner tubes are braced in the short direction, but with zero shearstiffness in the long direction.4.A single outer tube is supplied, which encircles the buildingperimeter.5.The outer tube is a moment-resisting frame, but with zero shearstiffness for the center50ft of each of the long sides.6.A space-truss hat structure is provided at the top of the building.7.A similar space truss is located near the bottom of the building8.The entire assembly is laterally supported at the base on twinsteel-plate tubes, because the shear stiffness of the outer tube goes to zero at the base of the building.Cellular structuresA classic example of a cellular structure is the Sears Tower, Chicago,a bundled tube structure of nine separate tubes. While the Sears Towercontains nine nearly identical tubes, the basic structural system has special application for buildings of irregular shape, as the several tubes need not be similar in plan shape, It is not uncommon that some of the individual tubes one of the strengths and one of the weaknesses of the system.This special weakness of this system, particularly in framed tubes, has to do with the concept of differential column shortening. The shortening of a column under load is given by the expression△=ΣfL/EFor buildings of 12 ft floor-to-floor distances and an average compressive stress of 15 ksi 138MPa, the shortening of a column under load is 15 1212/29,000 or per story. At 50 stories, the column will have shortened to in. 94mm less than its unstressed length. Where one cell of a bundled tube system is, say, 50stories high and an adjacent cell is, say, 100stories high, those columns near the boundary between .the two systems need to have this differential deflection reconciled.Major structural work has been found to be needed at such locations. In at least one building, the Rialto Project, Melbourne, the structural engineer found it necessary to vertically pre-stress the lower height columns so as to reconcile the differential deflections of columns in close proximity with the post-tensioning of the shorter column simulatingthe weight to be added on to adjacent, higher columns.二、原文翻译：抗侧向荷载的结构体系常用的结构体系若已测出荷载量达数千万磅重,那么在高层建筑设计中就没有多少可以进行极其复杂的构思余地了;确实,较好的高层建筑普遍具有构思简单、表现明晰的特点;这并不是说没有进行宏观构思的余地;实际上,正是因为有了这种宏观的构思,新奇的高层建筑体系才得以发展,可能更重要的是：几年以前才出现的一些新概念在今天的技术中已经变得平常了;如果忽略一些与建筑材料密切相关的概念不谈,高层建筑里最为常用的结构体系便可分为如下几类：1．抗弯矩框架;2．支撑框架,包括偏心支撑框架;3．剪力墙,包括钢板剪力墙;4．筒中框架;5．筒中筒结构;6．核心交互结构;7．框格体系或束筒体系;特别是由于最近趋向于更复杂的建筑形式,同时也需要增加刚度以抵抗几力和地震力,大多数高层建筑都具有由框架、支撑构架、剪力墙和相关体系相结合而构成的体系;而且,就较高的建筑物而言,大多数都是由交互式构件组成三维陈列;将这些构件结合起来的方法正是高层建筑设计方法的本质;其结合方式需要在考虑环境、功能和费用后再发展,以便提供促使建筑发展达到新高度的有效结构;这并不是说富于想象力的结构设计就能够创造出伟大建筑;正相反,有许多例优美的建筑仅得到结构工程师适当的支持就被创造出来了,然而,如果没有天赋甚厚的建筑师的创造力的指导,那么,得以发展的就只能是好的结构,并非是伟大的建筑;无论如何,要想创造出高层建筑真正非凡的设计,两者都需要最好的;虽然在文献中通常可以见到有关这七种体系的全面性讨论,但是在这里还值得进一步讨论;设计方法的本质贯穿于整个讨论;设计方法的本质贯穿于整个讨论中;抗弯矩框架抗弯矩框架也许是低,中高度的建筑中常用的体系,它具有线性水平构件和垂直构件在接头处基本刚接之特点;这种框架用作独立的体系,或者和其他体系结合起来使用,以便提供所需要水平荷载抵抗力;对于较高的高层建筑,可能会发现该本系不宜作为独立体系,这是因为在侧向力的作用下难以调动足够的刚度;我们可以利用STRESS,STRUDL 或者其他大量合适的计算机程序进行结构分析;所谓的门架法分析或悬臂法分析在当今的技术中无一席之地,由于柱梁节点固有柔性,并且由于初步设计应该力求突出体系的弱点,所以在初析中使用框架的中心距尺寸设计是司空惯的;当然,在设计的后期阶段,实际地评价结点的变形很有必要;支撑框架支撑框架实际上刚度比抗弯矩框架强,在高层建筑中也得到更广泛的应用;这种体系以其结点处铰接或则接的线性水平构件、垂直构件和斜撑构件而具特色,它通常与其他体系共同用于较高的建筑,并且作为一种独立的体系用在低、中高度的建筑中;尤其引人关注的是,在强震区使用偏心支撑框架;此外,可以利用STRESS,STRUDL,或一系列二维或三维计算机分析程序中的任何一种进行结构分析;另外,初步分析中常用中心距尺寸;剪力墙剪力墙在加强结构体系刚性的发展过程中又前进了一步;该体系的特点是具有相当薄的,通常是而不总是混凝土的构件,这种构件既可提供结构强度,又可提供建筑物功能上的分隔;在高层建筑中,剪力墙体系趋向于具有相对大的高宽经,即与宽度相比,其高度偏大;由于基础体系缺少应力,任何一种结构构件抗倾覆弯矩的能力都受到体系的宽度和构件承受的重力荷载的限制;由于剪力墙宽度狭狭窄受限,所以需要以某种方式加以扩大,以便提从所需的抗倾覆能力;在窗户需要量小的建筑物外墙中明显地使用了这种确有所需要宽度的体系;钢结构剪力墙通常由混凝土覆盖层来加强以抵抗失稳,这在剪切荷载大的地方已得到应用;这种体系实际上比钢支撑经济,对于使剪切荷载由位于地面正上方区域内比较高的楼层向下移特别有效;这种体系还具有高延性之优点,这种特性在强震区特别重要;由于这些墙内必然出同一些大孔,使得剪力墙体系分析变得错综复杂;可以通过桁架模似法、有限元法,或者通过利用为考虑剪力墙的交互作用或扭转功能设计的专门计处机程序进行初步分析框架或支撑式筒体结构：框架或支撑式筒体最先应用于IBM公司在Pittsburgh的一幢办公楼,随后立即被应用于纽约双子座的110层世界贸易中心摩天大楼和其他的建筑中;这种系统有以下几个显着的特征：三维结构、支撑式结构、或由剪力墙形成的一个性质上差不多是圆柱体的闭合曲面,但又有任意的平面构成;由于这些抵抗侧向荷载的柱子差不多都被设置在整个系统的中心,所以整体的惯性得到提高,刚度也是很大的;在可能的情况下,通过三维概念的应用、二维的类比,我们可以进行筒体结构的分析;不管应用那种方法,都必须考虑剪力滞后的影响;这种最先在航天器结构中研究的剪力滞后出现后,对筒体结构的刚度是一个很大的限制;这种观念已经影响了筒体结构在60层以上建筑中的应用;设计者已经开发出了很多的技术,用以减小剪力滞后的影响,这其中最有名的是桁架的应用;框架或支撑式筒体在40层或稍高的建筑中找到了自己的用武之地;除了一些美观的考虑外,桁架几乎很少涉及与外墙联系的每个建筑功能,而悬索一般设置在机械的地板上,这就令机械体系设计师们很不赞成;但是,作为一个性价比较好的结构体系,桁架能充分发挥它的性能,所以它会得到设计师们持续的支持;由于其最佳位置正取决于所提供的桁架的数量,因此很多研究已经试图完善这些构件的位置;实验表明：由于这种结构体系的经济性并不十分受桁架位置的影响,所以这些桁架的位置主要取决于机械系统的完善,审美的要求,筒中筒结构：筒体结构系统能使外墙中的柱具有灵活性,用以抵抗颠覆和剪切力;“筒中筒”这个名字顾名思义就是在建筑物的核心承重部分又被包围了第二层的一系列柱子,它们被当作是框架和支撑筒来使用;配置第二层柱的目的是增强抗颠覆能力和增大侧移刚度;这些筒体不是同样的功能,也就是说,有些筒体是结构的,而有些筒体是用来支撑的;在考虑这种筒体时,清楚的认识和区别变形的剪切和弯曲分量是很重要的,这源于对梁的对比分析;在结构筒中,剪切构件的偏角和柱、纵梁例如：结构筒中的网等的弯曲有关,同时,弯曲构件的偏角取决于柱子的轴心压缩和延伸例如：结构筒的边缘等;在支撑筒中,剪切构件的偏角和对角线的轴心变形有关,而弯曲构件的偏角则与柱子的轴心压缩和延伸有关;根据梁的对比分析,如果平面保持原形例如：厚楼板,那么外层筒中柱的轴心压力就会与中心筒柱的轴心压力相差甚远,而且稳定的大于中心筒;但是在筒中筒结构的设计中,当发展到极限时,内部轴心压力会很高的,甚至远远大于外部的柱子;这种反常的现象是由于两种体系中的剪切构件的刚度不同;这很容易去理解,内筒可以看成是一个支撑或者说是剪切刚性的筒,而外筒可以看成是一个结构或者说是剪切弹性的筒;核心交互式结构：核心交互式结构属于两个筒与某些形式的三维空间框架相配合的筒中筒特殊情况;事实上,这种体系常用于那种外筒剪切刚度为零的结构;位于Pittsburgh的美国钢铁大楼证实了这种体系是能很好的工作的;在核心交互式结构中,内筒是一个支撑结构,外筒没有任何剪切刚度,而且两种结构体系能通过一个空间结构或“帽”式结构共同起作用;需要指出的是,如果把外部的柱子看成是一种从“帽”到基础的直线体系,这将是不合适的；根据支撑核心的弹性曲线,这些柱子只发挥了刚度的15%;同样需要指出的是,内柱中与侧向力有关的轴向力沿筒高度由拉力变为压力,同时变化点位于筒高度的约5/8处;当然,外柱也传递相同的轴向力,这种轴向力低于作用在整个柱子高度的侧向荷载,因为这个体系的剪切刚度接近于零;把内外筒相连接的空间结构、悬臂梁或桁架经常遵照一些规范来布置;美国电话电报总局就是一个布置交互式构件的生动例子;1、结构体系长米,宽米,高米;2、布置了两个筒,每个筒的尺寸是米×米,在长方向上有米的间隔;3、在短方向上内筒被支撑起来,但是在长方向上没有剪切刚度;4、环绕着建筑物布置了一个外筒;5、外筒是一个瞬时抵抗结构,但是在每个长方向的中心米都没有剪切刚度;6、在建筑的顶部布置了一个空间桁架构成的“帽式”结构;7、在建筑的底部布置了一个相似的空间桁架结构;8、由于外筒的剪切刚度在建筑的底部接近零,整个建筑基本上由两个钢板筒来支持;框格体系或束筒体系结构：位于美国芝加哥的西尔斯大厦是箱式结构的经典之作,它由九个相互独立的筒组成的一个集中筒;由于西尔斯大厦包括九个几乎垂直的筒,而且筒在平面上无须相似,基本的结构体系在不规则形状的建筑中得到特别的应用;一些单个的筒高于建筑一点或很多是很常见的;事实上,这种体系的重要特征就在于它既有坚固的一面,也有脆弱的一面;这种体系的脆弱,特别是在结构筒中,与柱子的压缩变形有很大的关系,柱子的压缩变形有下式计算：△=ΣfL/E对于那些层高为米左右和平均压力为138MPa的建筑,在荷载作用下每层柱子的压缩变形为1512/29000或毫米;在第50层柱子会压缩94毫米,小于它未受压的长度;这些柱子在50层的时候和100层的时候的变形是不一样的,位于这两种体系之间接近于边缘的那些柱需要使这种不均匀的变形得以调解;主要的结构工作都集中在布置中;在Melbourne的Rialto项目中,结构工程师发现至少有一幢建筑,很有必要垂直预压低高度的柱子,以便使柱不均匀的变形差得以调解,调解的方法近似于后拉伸法,即较短的柱转移重量到较高的邻柱上;。
(完整版)土木工程专业英语课文原文及对照翻译
Civil EngineeringCivil engineering, the oldest of the engineering specialties, is the planning, design, construction, and management of the built environment. This environment includes all structures built according to scientific principles, from irrigation and drainage systems to rocket-launching facilities.土木工程学作为最老的工程技术学科，是指规划，设计，施工及对建筑环境的管理。
此处的环境包括建筑符合科学规范的所有结构，从灌溉和排水系统到火箭发射设施。
Civil engineers build roads, bridges, tunnels, dams, harbors, power plants, water and sewage systems, hospitals, schools, mass transit, and other public facilities essential to modern society and large population concentrations. They also build privately owned facilities such as airports, railroads, pipelines, skyscrapers, and other large structures designed for industrial, commercial, or residential use. In addition, civil engineers plan, design, and build complete cities and towns, and more recently have been planning and designing space platforms to house self-contained communities.土木工程师建造道路，桥梁，管道，大坝，海港，发电厂，给排水系统，医院，学校，公共交通和其他现代社会和大量人口集中地区的基础公共设施。
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外文文献及翻译题目：沉埋隧道工程对环境的影响专业土木工程学生姓名李鹏班级BM土木071学号**********指导教师殷勇沉埋隧道工程对环境的影响摘要：一座沉埋隧道对环境的深远影响都与穿过水道的沉放管段有关。
隧道对这一地区内地下和地表水的影响在隧道设计和施工方法的选择中起最重要的作用。
最近在考虑的一个影响施工的问题是必须为隧道开挖的沟槽有可能出现被污染的泥土。
挖出与运送这些泥土至专门装备起来以便接收它们的存放地点的方法是一系列重要新技术和质量控制措施的环境问题。
最常见的是在任何建筑工程中都会遇到的环境问题，即噪音、灰尘以及交通阻塞。
本文对这些问题以及目前用于解决这些问题的技术和措施作了评述。
关键词：隧道环境沉埋隧道的特征一座沉埋隧道具有两项基本特征：它是某一地下结构场地的一部分，要在繁忙的交通条件下保证施工，而并不意味这个地区是被充分地利用了的。
因此，施工空间是很宝贵的。
它基本上是一预制结构。
最终将安装在河流或运河底部位置的隧道管段是在其它地方以非常接近工厂条件的方式筑造的，这种条件在现场和工地是不大可能达到的。
施工规划上的优点和将管段制造与工地准备分开进行在后勤上的优点是显而易见的，还有极易于实现有效的质量控制的优点。
隧道工点在环境上的影响同样也大大少于隧道完全都在现场施工的情况；如像空间的需求和施工运输，这两个问题就大大的缓和。
当然，这些优点的先决条件是有现成的可用于管段制造的适宜工地。
它必须满足一系列有关环境影响的条件。
在如荷兰这类人口密集的国家里，要找到合适的工地很不容易，而且很显然，一旦选定一可用位置，可多次使用就相当引人。
因此，隧道施工的总体规划是一个供讨论的普通主题。
两端的地下结构一座新隧道连结到原来既有的地下结构中去，往往实际上是取代一既有的跨越水域的设施，如轮渡或桥梁。
它也可为一既有隧道或桥梁的补充设施。
无论决定建造一新隧道的理由如何，它的位置将在很大程度上受到既有地下结构布置的制约，而且其施工设计也要满足现有交通运输只受最小程度干扰的要求。
这就意味着设计人员在隧道位置方面很少有选择的机会，因而不得不根据这一既定位置的条件和要求来修改隧道设计。
这一情形主要影响连接隧道本身的引道部分。
然而，因为引道由穿过含水地层的分段组成，就有可能要求用新的措施以控制引道建造基坑排水影响的范围。
引道沉埋隧道几乎总是位于沉积地带，在那里，隧道引道降到地下水位以下。
在其完成时，它们是不透水的结构，周围的地下水不能渗入，存在的仅是单纯结构性质的环境影响。
然而在施工期间，环境问题则起着重要的作用。
为了建造起结构物，必须开挖一施工基坑直至地下水位以下若干米的深处，传统施工方法要求在施工期中持续不断把水排干。
除非采取进一步的措施，否则排水势必降低周围地区的水位，而且会导致一系列不希望的后果。
沉陷将发生，周围楼房和建筑物的基础将受到影响，而且甚至深桩基础也将受到沉陷土体经磨擦传递至桩上的额外向下荷载。
由于沉陷而堤坝高程下沉，而且农业地区的排水水位将会受到影响。
还有可能造成一种性质完全不同的环境问题：施工区域内的泥土可能被污染。
在这种情况下，施工基坑的开挖就要求格外注意，而且如有可能，就要采用诸如将泥土与水混合后经管道水力输送的特别方法。
还必须有一个经批准能容纳被污染泥土的地方。
必须采取若干措施以防止由于抽、排水而造成被污染泥土迅速分布到大面积地面上。
在技术上，总是可能消除这些各种各样的影响。
然而，由于做起来极为复杂而且会花费大量资金和时间，因此，目前倾向于寻找尽最大可能在水下建造引道和隧道进口的方法。
最理想的是，排空施工基坑中的水应该是一排干整个引道又完全不影响周围地下水位的单项作业。
明显的结论就是尽可能将施工基坑设计成最终产品的一部分。
引道边墙可设计成像有不透水芯墙的堤坝，其形式有泥浆墙、塑料板围幕或是常见的钢钣桩墙。
对最后一种形式增加其挡土的功能，就可节省有价值的空间，而且可容易地达到在水下与不透水底板的连接。
底板可以用水下混凝土建成。
这种方法已发展到能控制其高程和表面平整，以致达到在引道完全排干以后，只需要较少的修整工作。
另一种方法是采用不透水的塑料板材，加镇重安放于水下以盖住基坑底部和边坡。
在荷兰，这种方法不仅用于隧道的引道，而且用于公络的凹槽段。
使用大面积的塑料板材，以泥土作镇重安放到水下，用在一主要公路交叉口起到了长期的良好效果，它表明此技术已经推广使用。
不久，荷兰的隧道引道可能会向人们展示有茂盛的绿色边坡，从而取代了灰色的混凝土竖墙。
引道也可在别处预制并以浮运构件的形式安装。
此种方法只需用疏浚船开挖沟槽而完全不必排水。
不过目前还没有能充分处理浮力作用和基础问题的适宜设计。
管段制造上述对地下水与引道开挖之间的关系的讨论大部分都可以同样的方式应用于制造管段临时场地的开挖。
昂贵的解决办法给工程带来不合理的负担。
而且，这个制造管段的场地必须多次被附近的开阔水域淹没并打开以使预制成的隧道管段运至船坞处以便为另一些管段让出地方。
很少会有足够大的地方可供一次制造所有的管段。
总之，由于选择制造管段船坞的位置不像选择隧道引道的位置那样要严格地用功能要求来决定，故选择制造管段船坞的位置具有可以灵活的优点。
因此，制造船坞也就可以允许使用传统的排水法，如果由于上面列出的理由认为不允许使用传统的排水法时，而船坞又不得不与周围地下水分隔开时，这种地方使用不透水塑料板法由于其费用低就具有明显的优点。
另一种不影响周围地下水位的排水方法是"抽水回灌法"此法乃将渗入基坑的水用泵排出，又用泵将这些水通过过滤井管回灌到水的来源区。
只要渗透速度不是太大而且可保持大致是个常数，这个排、灌时闭路循环就可以保持。
这个新的措施，现在正用在荷兰的一个扩大的引道施工坑，由于这个基坑又要作为制造管段的船坞故加以扩大。
基槽的建造沉埋隧道的构槽是用疏浚法开挖的。
在本文中，我们只强调用疏浚法开挖基槽的要求能达到极高的精确度，而且这个要求将决定最适合这一工作设备的类型。
鉴于严格的定位容差，最好采用锚定疏浚船或在定位桩上的疏浚设备。
不过，由于它们不能自由移动，就可能成为船只航运的障碍。
假如在浚挖区域有水流或浪潮的影响，浚挖的基槽就会成为水流携带或沿河底推移的沉积物的积存处。
如果基槽开挖后长期不放置管段，就会很快形成淤积。
在上述情况下，基槽开挖和隧道管段安装两工序的相隔时间必须越短越好，因而对这两道工序的安排都需格外准确，可以采用一种专门的设备于安装管段之前清理基槽。
在荷兰，这种操作目前已发展到用在东斯格尔迪特防风暴海浪堤坝的墩柱安装中达到很高精度。
疏浚搅起了河底沉积物，造成在一定时间一定区域的河水浑浊。
最终这些成为悬浮的细颗粒物质会散开并重新逐渐沉淀下来。
尽管这一过程对环境的影响有限，而且无害，但在一定范围内还是日益受到强烈的抨击。
如果要浚挖的泥土是已被污染的，事情就更为复杂化，因为在这种条件下，浚挖作业就会使污染扩散。
现在浚挖技术已发展到通过使用一种专门的汲泥头来消除这一影响。
采用从浮船上下悬帘幕将浚挖区域与周围完全隔开的方法也可减少污染扩散。
在这一方面的进一步发展目前大家都注意到，在荷兰大部分水道底部都含有被污染的沉积物已很明显，因而浚挖这些泥土必然要承担一些特别的环境要求。
当前，这些要求尚未统一形成，而是针对每一具体工程提出不同的要求。
希望这种拖延关键技术发展的混乱局面能迅速得以解决。
根据污染的类型和程度，可将被污染泥土分为1～4类。
对于浚挖泥土（包括浚挖过程中的工艺用水）的弃置都按分类受到严格的限制；尤其是3和4类泥土都必须与外界隔绝，而且在可能的情况下加以净化。
在鹿特丹地区，已建成了一座储放这些固体废物以及其它有害物质的中心堆集场。
此外，第4类浚挖弃土被放在临时的较小的堆集点，待其被净化后再转放至别的隔离存放处。
在没有这类设施的地方，就必须按浚挖工程建立这种堆放点。
这一措施很明显需要做大量的工作。
管段的运输和安装疏浚工作和对航运的阻碍都是管段运输和安装带来的环境问题。
要打开管段制船坞和加深船坞与安装点之间航道的浅水域就需要浚挖作业。
前面有关浚挖的一些论述也适用这一情况。
安装工序中有一特殊的方面有可能涉及隧道基槽的最后清理。
为了使清理和安装两工序间隔时间缩至最短，在管段安放到其最终位置底部回填砂之前已成功地采用了射水法清理隧道管段基底。
用强力射水把要清除的最后一层沉积物冲成悬浮物，随后被水流带走。
在管段离开制造船坞，锚泊在临时码头和离开临时码头，浮运至安装点以及安装期间都有可能阻碍航运。
只有最后一道工序才会造成航运在短期内临时完全中断或部分中断。
在这个方面，一座沉埋隧道穿过一条河流与穿过一条运河存在着差别。
在后一种情况下，由于没有水流影响，就使得在沉放和安装用可更好地控制管段。
这种控制上的有利，就允许沉埋管段隧道采用更长管段单元，但这必须有足够大的制造船坞。
所以在荷兰，以往绝大多数沉埋隧道的管段单元长度都在100～150m之间变化，在跨越阿姆斯特丹和海域间北海运河的赫姆隧道（Hemtunnel）工程中还用了长达268m的管段单元。
使用较长的管段单元减少了安装作业的次数，从而也就减缓了对航运的阻碍。
对于沉埋管段隧道工程来说，妨碍航运似乎很适合定为一环境问题，但并不是一个重大问题。
回填这道工序包括用砂回填管段基底部，回填塞槽，以及必要时于管段顶部建造一冲刷防护层。
回填材料必须是未被污染的。
作业船在隧道上面施工时将干扰航运。
不过，通过用安装在隧道管段内的设备进行部分作业，就能减少这类麻烦，譬如经穿过隧道底部的孔口泵送砂、水混合物来回填等。
这一系统已在荷兰成功地应用过。
运营和维修涉及隧道运营的主要环境问题是通风。
由于清洁隧道边墙和维修路面要阻碍车辆运行，它们必须在适宜的时间内快速进行。
平整光滑的壁面以及良好的表涂层有助于清洁作业，从而也减少了限制车辆通过隧道的时间。
路面的建造必须做到能尽可能减少日后的维修。
Buried tunnel project on the environmentAbstract: a deeply buried tunnel far-reaching impact on the environment through the waterways with the sinking pipe related. Under the tunnel on the mainland in the region and the impact of surface water in the tunnel design and construction method of choice to play the most important role. In considering the impact of the recent construction of a problem is the need to trench excavation for the tunnel may appear to be contaminated soil. And transporting the excavated soil up to the specialized equipment in order to receive their storage place is a series of important new technologies and quality control measures for environmental problems. The most common is in any construction project will encounter environmental problems, namely, noise, dust and traffic congestion. In this paper, these issues and the current technology to address these issues and measures are discussed.Key words: tunnel environmentCharacteristics of a Buried deeply buried tunnel tunnel has twofundamental characteristics: (1) It is part of an underground structure of the site, to ensure that heavy traffic conditions, construction, and does not mean that this area is full use of The. Therefore, the construction space is very valuable.Will eventually be installed in the location of the river or canal bottom section of tunnel is very close in other areas to build manufacturing plants, ways, and this condition is unlikely in the field and reached the site. The advantages of planning and construction of pipe manufacture and the site will be ready to separate from the logistical advantages are obvious, there are extremely easy to implement effective quality control advantages.Tunnel work site on the environmental impact is also considerably less than the construction of the tunnel fully all the circumstances at the scene; such as space requirements and construction of transport, these two issues is greatly easing.Of course, a prerequisite for these benefits is a ready-made for pipe suitable site. It must meet the conditions for a series of environmental impact. In the Netherlands such as densely populated countries, to find a suitable site is not easy, but it is clear that once selected an available position, can be used repeatedly for quite a draw a crowd. Therefore, the overall plan for the tunnel construction is a common topic for discussion.Both ends of the structure of a new underground tunnel link to the original structure to the existing underground, often in fact across the waters to replace an existing facility, such as ferry or bridge. It can also be a complement existing facilities in tunnels or bridges. Whether the decision to build a new tunnel the reason, its location will be in large part by the constraints of existing underground structure layout, and its construction design must also meet the existing transport only by the requirements of minimal interference. This means that the location in the tunnel area designers rarely have a choice, and thus havethe position according to the established conditions and requirements to modify the tunnel design.This situation mainly affects the approach roads connecting part of the tunnel itself. However, because the approach road through the water by the formation of sub-components, it may require new measures to control the approaches to the scope of the construction pit drainage impact.Buried Tunnel approach roads are almost always located in the deposition zone, where the tunnel approach road down to the groundwater level below. At its completion, they are impervious structure, the surrounding water can not penetrate, there's just the nature of the environmental impact of a simple structure.However, during construction, environmental issues will play an important role. To build from the structures, construction of foundation must be excavated until the water table following a number of meters deep, the traditional construction method requires the construction period in the continuous draining of the water. Unless further measures, or drainage will definitely lower the water level in the surrounding area, and will lead to a series of undesirable consequences. Subsidence will occur, based on the surrounding buildings and structures will be affected, and even deep pile foundation soil settlement will also be passed by the friction down to the pile on the extra load. Subsidence and elevation of the dam sinking, and agricultural drainage water will be affected.May also result in a completely different nature of environmental problems: the construction area may be contaminated soil. In this case, the construction of the excavation pit special attention to requirements and, if possible, should be used, such as soil mixed with water and water transport by pipeline, special methods. There must also be able to accommodate an approved place of contaminated soil.Number of measures must be taken to prevent the pumping of contaminated water caused by the rapid distribution of the soil to a large area on the ground.Technically speaking, is always possible to eliminate the impact of these kinds. However, it is extremely complex and do take a lot of moneyand time, therefore, tend to look at present the greatest extent possible the construction of approach roads and tunnels in the water imported methods. Ideally, the empty pit in the construction of a drainage of water should be no impact on the approach roads and the surrounding groundwater single operation.The obvious conclusion is that as far as possible the construction pit designed as part of the final product.Approach a wall can be designed to image the wall of the dam impervious core in the form of a slurry wall, curtain or plastic sheet of steel sheet pile walls common. On the final form (steel sheet pile wall) (off panel through the use of heavy anchor piles and soil) to increase its retaining function, you can save valuable space and can be easily achieved in the water and impermeable floor connection.Water under the concrete floor can be built. This approach has been developed to control the elevation and surface roughness, which completely drained to the approach road after finishing requires less work.Another method is the use of impermeable plastic sheet, add water to the town of emphasis placed on the bottom and cover the pit slope. In the Netherlands, this approach not only for the tunnel approaches, and the groove for the public network segment.Use large plastic sheet, to the soil to the water for the town re-placed by a major highway intersection in the play a long-term good results, it shows that this technology has been widely used. Soon, the Netherlands, the tunnel approach roads may be to show a lush green slope, thereby replacing the gray concrete vertical wall.Approach can also be prefabricated elsewhere and in the form of installation of floating structures. This method only with trench excavation and dredging vessels do not have to drain. But not yet able to adequately address basic problems of buoyancy and appropriate design. Buried tunnel project on the environmentPipe manufacturing approaches to the excavation of underground water and the discussion of the relationship between the way the majority can be used to produce the same pipe excavation of the temporary venues.Expensive solution to bring an unreasonable burden to the project. Moreover, the manufacture of pipe near the site have repeatedly flooded the open waters and open to the precast tunnel segments into the transportation to the dock at the other pipe section in order to make room. Rarely a large enough place for all of the pipe manufacturer.In short, the choice of the location of manufacturing pipe dock not chosen as the location of the tunnel approach roads to be strictly determined by functional requirements, so choose the location of manufacturing pipe dock with the advantages of flexibility. Therefore, the manufacture of docks will be allowed to use the traditional water method, if the reasons listed above that do not allow the use of traditional water law, and the dock had to separate from the surrounding water, this places impermeable plastic plate because of its low cost to have obvious advantages.Another does not affect the drainage around the water table is "pumping recharge Law" This law is the foundation of the water into the pump discharge and pump water through the filter of these tube wells to the water source recharge area. As long as the penetration rate is not too large and can be maintained roughly a constant, the row, when the closed-loop irrigation can be maintained. The new measures, now being expanded in the Netherlands approaches to the construction of a pit, but also because the foundation of the dock as the manufacture of pipe it to be expanded.Construction of foundation trench trough structure deeply buried tunnel excavation method is dredging. In this paper, we only stress the importance of dredging requirements of foundation trench excavation method can achieve high accuracy, and this requires that the work will determine the most suitable type of device. Given the strict positioning tolerances, preferably dredging boat anchor or pile in positioning the dredging equipment. However, because they can not move freely, it could become an obstacle to shipping vessels.If there is water in the dredging area, or the wave of the impact of dredging will become the base slot to carry water along the bottom or盐城工学院本科毕业生毕业设计说明书2010sediment accumulation over the place. If the foundation trench excavation in place pipe for long periods, it will soon form a deposition. In these circumstances, the base section of tank excavation and tunnel installation of the interval between the two processes must be as short as possible, and thus the arrangement of the two procedure are to be particularly accurate, you can use a special device to clean the base before the installation of pipe slot. In the Netherlands, this operation has been developed to be used in the East (Eastern Scheldt) anti-dam pier storm waves reach a very high precision installation.Dredging stir up the river sediments, resulting in a certain time a certain area of the water turbidity. Eventually become a suspended fine particles of these substances will spread out and gradually settle down again. Although this process had limited impact on the environment, and harmless, but in a certain range or the increasingly strong criticism.If you want to have dredged soil is contaminated, it is even more complicated, because in such conditions, the dredging operation will cause the spread of contamination. Dredging technology has now developed to the drain by using a special mud head to eliminate this effect. Under the floating boat by hanging curtains from the dredging area will be completely separated from the surrounding method may also reduce the spread of pollution.Further development in this regard we have taken note of the current, most waterways in the Netherlands contain contaminated bottom sediments have been very clear, so dredging the mud is bound to take some special environmental requirements.Currently, these requirements have not been unified to form, but made different for each specific project requirements. Hope that this delay in the development of key technologies of the chaos can be quickly resolved.According to the type and extent of contamination, contaminated soil can be divided into 1 to 4 classes. For dredging mud (including dredging process water in the process) and disposal are subject to strict restrictions by category; particular, 3 and 4 the soil must be isolated,- 11 -沉埋隧道工程对环境的影响and in possible to be purified.In the Rotterdam area, has built a store of these solid waste and other hazardous substances the center of the dump site. In addition, Type 4 is placed in temporary dredging spoil heap smaller point, let it be purified and then transferred to another isolated place repository. Place in the absence of such facilities to be established by dredging this dump sites. This measure is a clear need to do a lot of work.Transportation and installation of pipe work and dredging the shipping obstacles to transport and install pipe sections are brought about environmental problems. To open the pipe system and installation of marinas and docks to deepen the shallow waters between the points need to channel dredging operations. Some of the previous discussion about dredging also apply to this situation.The installation procedures in a particular area may involve the end of the tunnel-based clean-up slot. To make clean-up and installation of the two processes reduce to a minimum interval of time, placed in the pipe to its final position before the bottom of the sand filling has been successfully used to shoot clean water law section of the base tunnel. With a powerful water jet to remove the last layer of the sediment washed into the suspension, followed by water flow away.Left in the pipe manufacturing dock, anchored at the temporary terminal and leave the temporary pier, floating point and transported to the installation during installation are likely to hinder shipping. Only the last one caused by the shipping process will complete in the short term temporary interruption or partial interruption.In this respect, a deeply buried tunnel across a river and there are differences across a canal. In the latter case, the absence of flow effects to make the sinking and installation of pipe can be better controlled. The advantage of this control to allow the use of more deeply buried sections of the tunnel tube pipe unit, but it must be large enough to create dock.Therefore, in the Netherlands, in the past most deeply buried pipe unit length of the tunnel are varied between 100 ~ 150m, crossing the North- 12 -盐城工学院本科毕业生毕业设计说明书2010Sea Canal between Amsterdam and the Trondheim area tunnel (Hemtunnel) project has also used the unit for up to 268m of pipe . Use a longer pipe unit reduces the number of installation, which will slow down the barriers to shipping.Buried pipe for the tunnel project, it seems to impede the shipping for the environment as a problem, but not a major problem.This process includes filling with sand filling pipe at the base, back to the filling tank, and, if necessary in the pipe at the top of the construction of a scour protection layer.Backfill material must be uncontaminated. Ship in the tunnel construction work will interfere with the above shipping. However, by using a pipe installed in the tunnel were part of the operation of equipment, we can reduce such problems, for example, through the tunnel at the bottom of the holes by pumping sand and water mixture to backfilling. This system has been successfully applied in the Netherlands.Tunnel operation and maintenance operations involving major environmental issue is ventilation.Cleaning and maintenance of the tunnel wall to obstruct the road vehicle operation, they must be in the appropriate period of time quickly. Smooth wall and good coating helps to clean the operating table, thus reducing the time limit traffic through the tunnel.Road construction must be done to minimize future maintenance.- 13 -。