土木工程外文翻译70683
土木工程毕业设计外文翻译原文+翻译
The bridge crack produced the reason to simply analyseIn recent years, the traffic capital construction of our province gets swift and violent development, all parts have built a large number of concrete bridges. In the course of building and using in the bridge, relevant to influence project quality lead of common occurrence report that bridge collapse even because the crack appears The concrete can be said to " often have illness coming on " while fracturing and " frequently-occurring disease ", often perplex bridge engineers and technicians. In fact , if take certain design and construction measure, a lot of cracks can be overcome and controlled. For strengthen understanding of concrete bridge crack further, is it prevent project from endanger larger crack to try one's best, this text make an more overall analysis , summary to concrete kind and reason of production , bridge of crack as much as possible, in order to design , construct and find out the feasible method which control the crack , get the result of taking precautions against Yu WeiRan.Concrete bridge crack kind, origin cause of formation In fact, the origin cause of formation of the concrete structure crack is complicated and various, even many kinds of factors influence each other , but every crack has its one or several kinds of main reasons produced . The kind of the concrete bridge crack, on its reason to produce, can roughly divide several kinds as follows :(1) load the crack caused Concrete in routine quiet .Is it load to move and crack that produce claim to load the crack under the times of stress bridge, summing up has direct stress cracks , two kinds stress crack onces mainly. Direct stress crack refer to outside load direct crack that stress produce that cause. The reason why the crack produces is as follows, 1, Design the stage of calculating , does not calculate or leaks and calculates partly while calculating in structure; Calculate the model is unreasonable; The structure is supposed and accorded with by strength actually by strength ; Load and calculate or leak and calculate few; Internal force and matching the mistake in computation of muscle; Safety coefficient of structure is not enough. Do not consider the possibility that construct at the time of the structural design; It is insufficientto design the section; It is simply little and assigning the mistake for reinforcing bar to set up; Structure rigidity is insufficient; Construct and deal with improperly; The design drawing can not be explained clearly etc.. 2, Construction stage, does not pile up and construct the machines , material limiting ; Is it prefabricate structure structure receive strength characteristic , stand up , is it hang , transport , install to get up at will to understand; Construct not according to the design drawing, alter the construction order of the structure without authorization , change the structure and receive the strength mode; Do not do the tired intensity checking computations under machine vibration and wait to the structure . 3, Using stage, the heavy-duty vehicle which goes beyond the design load passes the bridge; Receive the contact , striking of the vehicle , shipping; Strong wind , heavy snow , earthquake happen , explode etc.. Stress crack once means the stress of secondary caused by loading outside produces the crack. The reason why the crack produces is as follows, 1, In design outside load function , because actual working state and routine , structure of thing calculate have discrepancy or is it consider to calculate, thus cause stress once to cause the structure to fracture in some position. Two is it join bridge arch foot is it is it assign " X " shape reinforcing bar , cut down this place way , section of size design and cut with scissors at the same time to adopt often to design to cut with scissors, theory calculate place this can store curved square in , but reality should is it can resist curved still to cut with scissors, so that present the crack and cause the reinforcing bar corrosion. 2, Bridge structure is it dig trough , turn on hole , set up ox leg ,etc. to need often, difficult to use a accurate one diagrammatic to is it is it calculate to imitate to go on in calculating in routine, set up and receive the strength reinforcing bar in general foundation experience. Studies have shown , after being dug the hole by the strength component , it will produce the diffraction phenomenon that strength flows, intensive near the hole in a utensil, produced the enormous stress to concentrate. In long to step prestressing force of the continuous roof beam , often block the steel bunch according to the needs of section internal force in stepping, set up the anchor head, but can often see the crack in the anchor firm section adjacent place. So if deal with improper, in corner or component form sudden change office , block place to be easy to appear crack strengthreinforcing bar of structure the. In the actual project, stress crack once produced the most common reason which loads the crack. Stress crack once belong to one more piece of nature of drawing , splitting off , shearing. Stress crack once is loaded and caused, only seldom calculate according to the routine too, but with modern to calculate constant perfection of means, times of stress crack to can accomplish reasonable checking computations too. For example to such stresses 2 times of producing as prestressing force , creeping ,etc., department's finite element procedure calculates levels pole correctly now, but more difficult 40 years ago. In the design, should pay attention to avoiding structure sudden change (or section sudden change), when it is unable to avoid , should do part deal with , corner for instance, make round horn , sudden change office make into the gradation zone transition, is it is it mix muscle to construct to strengthen at the same time, corner mix again oblique to reinforcing bar , as to large hole in a utensil can set up protecting in the perimeter at the terms of having angle steel. Load the crack characteristic in accordance with loading differently and presenting different characteristics differently. The crack appear person who draw more, the cutting area or the serious position of vibration. Must point out , is it get up cover or have along keep into short crack of direction to appear person who press, often the structure reaches the sign of bearing the weight of strength limit, it is an omen that the structure is destroyed, its reason is often that sectional size is partial and small. Receive the strength way differently according to the structure, the crack characteristic produced is as follows: 1, The centre is drawn. The crack runs through the component cross section , the interval is equal on the whole , and is perpendicular to receiving the strength direction. While adopting the whorl reinforcing bar , lie in the second-class crack near the reinforcing bar between the cracks. 2, The centre is pressed. It is parallel on the short and dense parallel crack which receive the strength direction to appear along the component. 3, Receive curved. Most near the large section from border is it appear and draw into direction vertical crack to begin person who draw curved square, and develop toward neutralization axle gradually. While adopting the whorl reinforcing bar , can see shorter second-class crack among the cracks. When the structure matches muscles less, there are few but wide cracks, fragility destruction may take place in thestructure 4, Pressed big and partial. Heavy to press and mix person who draw muscle a less one light to pigeonhole into the component while being partial while being partial, similar to receiving the curved component. 5, Pressed small and partial. Small to press and mix person who draw muscle a more one heavy to pigeonhole into the component while being partial while being partial, similar to the centre and pressed the component. 6, Cut. Press obliquly when the hoop muscle is too dense and destroy, the oblique crack which is greater than 45?? direction appears along the belly of roof beam end; Is it is it is it destroy to press to cut to happen when the hoop muscle is proper, underpart is it invite 45?? direction parallel oblique crack each other to appear along roof beam end. 7, Sprained. Component one side belly appear many direction oblique crack, 45?? of treaty, first, and to launch with spiral direction being adjoint. 8, Washed and cut. 4 side is it invite 45?? direction inclined plane draw and split to take place along column cap board, form the tangent plane of washing. 9, Some and is pressed. Some to appear person who press direction roughly parallel large short cracks with pressure.(2) crack caused in temperature changeThe concrete has nature of expanding with heat and contract with cold, look on as the external environment condition or the structure temperature changes, concrete take place out of shape, if out of shape to restrain from, produce the stress in the structure, produce the temperature crack promptly when exceeding concrete tensile strength in stress. In some being heavy to step foot-path among the bridge , temperature stress can is it go beyond living year stress even to reach. The temperature crack distinguishes the main characteristic of other cracks will be varied with temperature and expanded or closed up. The main factor is as follows, to cause temperature and change 1, Annual difference in temperature. Temperature is changing constantly in four seasons in one year, but change relatively slowly, the impact on structure of the bridge is mainly the vertical displacement which causes the bridge, can prop up seat move or set up flexible mound ,etc. not to construct measure coordinate , through bridge floor expansion joint generally, can cause temperature crack only when the displacement of the structure is limited, for example arched bridge , just bridge etc. The annual difference in temperature of our country generally changes therange with the conduct of the average temperature in the moon of January and July. Considering the creep characteristic of the concrete, the elastic mould amount of concrete should be considered rolling over and reducing when the internal force of the annual difference in temperature is calculated. 2, Rizhao. After being tanned by the sun by the sun to the side of bridge panel , the girder or the pier, temperature is obviously higher than other position, the temperature gradient is presented and distributed by the line shape . Because of restrain oneself function, cause part draw stress to be relatively heavy, the crack appears. Rizhao and following to is it cause structure common reason most , temperature of crack to lower the temperature suddenly 3, Lower the temperature suddenly. Fall heavy rain , cold air attack , sunset ,etc. can cause structure surface temperature suddenly dropped suddenly, but because inside temperature change relatively slow producing temperature gradient. Rizhao and lower the temperature internal force can adopt design specification or consult real bridge materials go on when calculating suddenly, concrete elastic mould amount does not consider converting into and reducing 4, Heat of hydration. Appear in the course of constructing, the large volume concrete (thickness exceeds 2. 0), after building because cement water send out heat, cause inside very much high temperature, the internal and external difference in temperature is too large, cause the surface to appear in the crack. Should according to actual conditions in constructing, is it choose heat of hydration low cement variety to try one's best, limit cement unit's consumption, reduce the aggregate and enter the temperature of the mould , reduce the internal and external difference in temperature, and lower the temperature slowly , can adopt the circulation cooling system to carry on the inside to dispel the heat in case of necessity, or adopt the thin layer and build it in succession in order to accelerate dispelling the heat. 5, The construction measure is improper at the time of steam maintenance or the winter construction , the concrete is sudden and cold and sudden and hot, internal and external temperature is uneven , apt to appear in the crack. 6, Prefabricate T roof beam horizontal baffle when the installation , prop up seat bury stencil plate with transfer flat stencil plate when welding in advance, if weld measure to be improper, iron pieces of nearby concrete easy to is it fracture to burn. Adopt electric heat piece draw law piece draw prestressing force at the component ,prestressing force steel temperature can rise to 350 degrees Centigrade , the concrete component is apt to fracture. Experimental study indicates , are caused the intensity of concrete that the high temperature burns to obviously reduce with rising of temperature by such reasons as the fire ,etc., glueing forming the decline thereupon of strength of reinforcing bar and concrete, tensile strength drop by 50% after concrete temperature reaches 300 degrees Centigrade, compression strength drops by 60%, glueing the strength of forming to drop by 80% of only round reinforcing bar and concrete; Because heat, concrete body dissociate ink evaporate and can produce and shrink sharply in a large amount(3) shrink the crack causedIn the actual project, it is the most common because concrete shrinks the crack caused. Shrink kind in concrete, plasticity shrink is it it shrinks (is it contract to do ) to be the main reason that the volume of concrete out of shape happens to shrink, shrink spontaneously in addition and the char shrink. Plasticity shrink. About 4 hours after it is built that in the course of constructing , concrete happens, the cement water response is fierce at this moment, the strand takes shape gradually, secrete water and moisture to evaporate sharply, the concrete desiccates and shrinks, it is at the same time conduct oneself with dignity not sinking because aggregate,so when harden concrete yet,it call plasticity shrink. The plasticity shrink producing amount grade is very big, can be up to about 1%. If stopped by the reinforcing bar while the aggregate sinks, form the crack along the reinforcing bar direction. If web , roof beam of T and roof beam of case and carry baseplate hand over office in component vertical to become sectional place, because sink too really to superficial obeying the web direction crack will happen evenly before hardenning. For reducing concrete plasticity shrink,it should control by water dust when being construct than,last long-time mixing, unloading should not too quick, is it is it take closely knit to smash to shake, vertical to become sectional place should divide layer build. Shrink and shrink (do and contract). After the concrete is formed hard , as the top layer moisture is evaporated progressively , the humidity is reduced progressively , the volume of concrete is reduced, is called and shrunk to shrink (do and contract). Because concrete top layermoisture loss soon, it is slow for inside to lose, produce surface shrink heavy , inside shrink a light one even to shrink, it is out of shape to restrain from by the inside concrete for surface to shrink, cause the surface concrete to bear pulling force, when the surface concrete bears pulling force to exceed its tensile strength, produce and shrink the crack. The concrete hardens after-contraction to just shrink and shrink mainly .Such as mix muscle rate heavy component (exceed 3% ), between reinforcing bar and more obvious restraints relatively that concrete shrink, the concrete surface is apt to appear in the full of cracks crackle. Shrink spontaneously. Spontaneous to it shrinks to be concrete in the course of hardenning , cement and water take place ink react, the shrink with have nothing to do by external humidity, and can positive (whether shrink, such as ordinary portland cement concrete), can negative too (whether expand, such as concrete, concrete of slag cement and cement of fly ash). The char shrinks. Between carbon dioxide and hyrate of cement of atmosphere take place out of shape shrink that chemical reaction cause. The char shrinks and could happen only about 50% of humidity, and accelerate with increase of the density of the carbon dioxide. The char shrinks and seldom calculates . The characteristic that the concrete shrinks the crack is that the majority belongs to the surface crack, the crack is relatively detailed in width , and criss-cross, become the full of cracks form , the form does not have any law . Studies have shown , influence concrete shrink main factor of crack as follows, 1, Variety of cement , grade and consumption. Slag cement , quick-hardening cement , low-heat cement concrete contractivity are relatively high, ordinary cement , volcanic ash cement , alumina cement concrete contractivity are relatively low. Cement grade low in addition, unit volume consumption heavy rubing detailed degree heavy, then the concrete shrinks the more greatly, and shrink time is the longer. For example, in order to improve the intensity of the concrete , often adopt and increase the cement consumption method by force while constructing, the result shrinks the stress to obviously strengthen . 2, Variety of aggregate. Such absorbing water rates as the quartz , limestone , cloud rock , granite , feldspar ,etc. are smaller, contractivity is relatively low in the aggregate; And such absorbing water rates as the sandstone , slate , angle amphibolite ,etc. are greater, contractivity is relatively high. Aggregate grains of foot-path heavy to shrink light inaddition, water content big to shrink the larger. 3, Water gray than. The heavier water consumption is, the higher water and dust are, the concrete shrinks the more greatly. 4, Mix the pharmaceutical outside. It is the better to mix pharmaceutical water-retaining property outside, then the concrete shrinks the smaller. 5, Maintain the method . Water that good maintenance can accelerate the concrete reacts, obtain the intensity of higher concrete. Keep humidity high , low maintaining time to be the longer temperature when maintaining, then the concrete shrinks the smaller. Steam maintain way than maintain way concrete is it take light to shrink naturall. 6, External environment. The humidity is little, the air drying , temperature are high, the wind speed is large in the atmosphere, then the concrete moisture is evaporated fast, the concrete shrinks the faster. 7, Shake and smash the way and time. Machinery shake way of smashing than make firm by ramming or tamping way concrete contractivity take little by hand. Shaking should determine according to mechanical performance to smash time , are generally suitable for 55s / time. It is too short, shake and can not smash closely knit , it is insufficient or not even in intensity to form the concrete; It is too long, cause and divide storey, thick aggregate sinks to the ground floor, the upper strata that the detailed aggregate stays, the intensity is not even , the upper strata incident shrink the crack. And shrink the crack caused to temperature, worthy of constructing the reinforcing bar againing can obviously improve the resisting the splitting of concrete , structure of especially thin wall (thick 200cm of wall ). Mix muscle should is it adopt light diameter reinforcing bar (8 |? construct 14 |? ) to have priority , little interval assign (whether @ 10 construct @ 15cm ) on constructing, the whole section is it mix muscle to be rate unsuitable to be lower than 0 to construct. 3%, can generally adopt 0 . 3%~0. 5%.(4), crack that causes out of shape of plinth of the groundBecause foundation vertical to even to subside or horizontal direction displacement, make the structure produce the additional stress, go beyond resisting the ability of drawing of concrete structure, cause the structure to fracture. The even main reason that subside of the foundation is as follows, 1, Reconnoitres the precision and is not enough for , test the materials inaccuratly in geology. Designing, constructing without fully grasping the geological situation, this is the main reason that cause the ground not to subside evenly .Such as hills area or bridge, district of mountain ridge,, hole interval to be too far when reconnoitring, and ground rise and fall big the rock, reconnoitring the report can't fully reflect the real geological situation . 2, The geological difference of the ground is too large. Building it in the bridge of the valley of the ditch of mountain area, geology of the stream place and place on the hillside change larger, even there are weak grounds in the stream, because the soil of the ground does not causes and does not subside evenly with the compressing. 3, The structure loads the difference too big. Under the unanimous terms, when every foundation too heavy to load difference in geological situation, may cause evenly to subside, for example high to fill out soil case shape in the middle part of the culvert than to is it take heavy to load both sides, to subside soon heavy than both sides middle part, case is it might fracture to contain 4, The difference of basic type of structure is great. Unite it in the bridge the samly , mix and use and does not expand the foundation and a foundation with the foundation, or adopt a foundation when a foot-path or a long difference is great at the same time , or adopt the foundation of expanding when basis elevation is widely different at the same time , may cause the ground not to subside evenly too 5, Foundation built by stages. In the newly-built bridge near the foundation of original bridge, if the half a bridge about expressway built by stages, the newly-built bridge loads or the foundation causes the soil of the ground to consolidate again while dealing with, may cause and subside the foundation of original bridge greatly 6, The ground is frozen bloatedly. The ground soil of higher moisture content on terms that lower than zero degree expands because of being icy; Once temperature goes up , the frozen soil is melted, the setting of ground. So the ground is icy or melts causes and does not subside evenly . 7, Bridge foundation put on body, cave with stalactites and stalagmites, activity fault,etc. of coming down at the bad geology, may cause and does not subside evenly . 8, After the bridge is built up , the condition change of original ground . After most natural grounds and artificial grounds are soaked with water, especially usually fill out such soil of special ground as the soil , loess , expanding in the land ,etc., soil body intensity meet water drop, compress out of shape to strengthen. In the soft soil ground , season causes the water table to drop to draw water or arid artificially, the ground soil layer consolidates and sinks again,reduce the buoyancy on the foundation at the same time , shouldering the obstruction of rubing to increase, the foundation is carried on one's shoulder or back and strengthened .Some bridge foundation is it put too shallow to bury, erode , is it dig to wash flood, the foundation might be moved. Ground load change of terms, bridge nearby is it is it abolish square , grit ,etc. in a large amount to put to pile with cave in , landslide ,etc. reason for instance, it is out of shape that the bridge location range soil layer may be compressed again. So, the condition of original ground change while using may cause and does not subside evenly Produce the structure thing of horizontal thrust to arched bridge ,etc., it is the main reason that horizontal displacement crack emerges to destroy the original geological condition when to that it is unreasonable to grasp incompletely , design and construct in the geological situation.桥梁裂缝产生原因浅析近年来，我省交通基础建设得到迅猛发展，各地建立了大量的混凝土桥梁。
土木工程 外文文献翻译
学院：专业：土木工程姓名：学号：外文出处： Structural Systems to resist (用外文写)Lateral loads附件： 1.外文资料翻译译文；2.外文原文。
附件1：外文资料翻译译文抗侧向荷载的结构体系常用的结构体系若已测出荷载量达数千万磅重，那么在高层建筑设计中就没有多少可以进行极其复杂的构思余地了。
确实，较好的高层建筑普遍具有构思简单、表现明晰的特点。
这并不是说没有进行宏观构思的余地。
实际上，正是因为有了这种宏观的构思，新奇的高层建筑体系才得以发展，可能更重要的是：几年以前才出现的一些新概念在今天的技术中已经变得平常了。
如果忽略一些与建筑材料密切相关的概念不谈，高层建筑里最为常用的结构体系便可分为如下几类：1.抗弯矩框架。
2.支撑框架，包括偏心支撑框架。
3.剪力墙，包括钢板剪力墙。
4.筒中框架。
5.筒中筒结构。
6.核心交互结构。
7. 框格体系或束筒体系。
特别是由于最近趋向于更复杂的建筑形式，同时也需要增加刚度以抵抗几力和地震力，大多数高层建筑都具有由框架、支撑构架、剪力墙和相关体系相结合而构成的体系。
而且，就较高的建筑物而言，大多数都是由交互式构件组成三维陈列。
将这些构件结合起来的方法正是高层建筑设计方法的本质。
其结合方式需要在考虑环境、功能和费用后再发展，以便提供促使建筑发展达到新高度的有效结构。
这并不是说富于想象力的结构设计就能够创造出伟大建筑。
正相反，有许多例优美的建筑仅得到结构工程师适当的支持就被创造出来了，然而，如果没有天赋甚厚的建筑师的创造力的指导，那么，得以发展的就只能是好的结构，并非是伟大的建筑。
无论如何，要想创造出高层建筑真正非凡的设计，两者都需要最好的。
虽然在文献中通常可以见到有关这七种体系的全面性讨论，但是在这里还值得进一步讨论。
设计方法的本质贯穿于整个讨论。
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。
土木工程外文翻译70683
本科毕业设计（论文）外文翻译译文学生姓名：院 （系）：专业班级：指导教师：完成日期：钢筋混凝土填充框架结构对拆除两个相邻的柱的响应作者： 美国波士顿东北大学，斯奈尔 设计中心收稿日期： 年 月 日，修整后收稿日期 年 月 日，录用日期 年 月 日，网上上传日期 年 月 日。
摘要：本文是评价圣地亚哥旅馆对同时拆除两根相邻的外柱的响应问题，圣地亚哥旅馆是个 层钢筋混凝土填充框架结构。
结构的分析模型应用了有限元法和以此为基础的分析模型来计算结构的整体和局部变形。
分析结果跟实验结果非常吻合。
当测量的竖向位移增加到为四分之一英寸（即 ）的时候，结构就发生连续倒塌。
通过实验分析方法评价和讨论随着柱的移除而产生的变形沿着结构高度上的发展和荷载动态重分配。
讨论了轴向和弯曲的变形传播的不同。
结构横向和纵向的三维桁架在填充墙的参与下被认为是荷载重分配的主要构件。
讨论了两种潜在的脆性破坏模型（没有拉力加强的梁的脆断和有加筋肋的梁的挤出）。
分析评价了结构对额外的重力和无填充墙时的响应。
有限责任公司对此文保留所有权利。
关键词：连续倒塌；荷载重分配；对荷载抵抗能力；动态响应；非线性分析；脆性破坏。
介绍：作为减小由于结构的局部损坏而造成大量伤亡的可能性措施的一部分，美国总务管理局【 】和国防部【 】出台了一系列制度来评价结构对连续倒塌的抵抗力。
【 】定义连续倒塌为，由原始单元的局部破坏在单元间的扩展最终造成结构的整体或不成比例的大部破坏。
通过 和 【 】建议的方法， 定义了两种一般模型来减小结构设计时连续倒塌效应产生的损害，它们分为直接和间接的设计方法。
一般建筑规范和标准用增加结构的整体性的间接设计方法。
间接设计法也应用于美国国防部的降低连续倒塌设计和未归档设备标准中。
尽管间接设计法可以降低连续破坏的风险【 ， 】，对基于此法设计的结构破坏后的表现的判断是不容易实现的。
有一种基于直接设计的方法通过研究瞬间消除受载构件，比如柱子，对结构的影响来评价结构的连续倒塌。
土木工程概论外文翻译.doc
外文原文 2Civil engineering introduction papersAbstract: 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 building 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 Engineering, because they all have Min Yong Xing. 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, water and 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 bearingcapacity 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 technology improves gradually developed. In ancient times, the human lives, the line USES is the rocks and trees. 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 Sheltie 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 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 enhanceChina'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 the interaction 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 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 beautiful enjoying, 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 moreimportant 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 estimated to build, insert roller skyscrapers, across the ocean Bridges, 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 more comfortable living environment. With 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 thousands 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, theleast 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.中文翻译2土木工程概论摘要：土木工程是一门庞大大学科，主要的部分是建筑，无论在国内还是在国外，都有着悠久的历史发展过程。
土木工程专业毕业设计外文翻译
Building construction concrete crack of prevention and processingAbstractThe crack problem of concrete is a widespread existence but again difficult in solve of engineering actual problem, this text carried on a study analysis to a little bit familiar crack problem in the concrete engineering, and aim at concrete the circumstance put forward some prevention, processing measure. Keyword:Concrete crack prevention processing ForewordConcrete's ising 1 kind is anticipate by the freestone bone, cement, water and other mixture but formation of the in addition material of quality brittleness not and all material.Because the concrete construction transform with oneself, control etc. a series problem, harden model of in the concrete existence numerous tiny hole, spirit cave and tiny crack, is exactly because these beginning start blemish of existence just make the concrete present one some not and all the characteristic of quality.The tiny crack is a kind of harmless crack and accept concrete heavy, defend Shen and a little bit other use function not a creation to endanger.But after the concrete be subjected to lotus carry, difference in temperature etc. function, tiny crack would continuously of expand with connect, end formation we can see without the aid of instruments of macro view the crack be also the crack that the concrete often say in the engineering. Concrete building and Gou piece usually all take sewer to make of, because of crack of existence and development usually make inner part of reinforcing bar etc. material creation decay, lower reinforced concrete material of loading ability, durable and antiShen ability, influence building of external appearance, service life, severity will threat arrive people's life and property safety.A lot of all of crash of engineerings is because of the unsteady development of the crack with the result that.Modern age science research with a great deal of of the concrete engineering practice certificate, in the concrete engineering crack problem is ineluctable, also acceptable in certainly of the scope just need to adopt valid of measure will it endanger degree control at certain of scope inside.The reinforced concrete norm is also explicit provision:Some structure at place of dissimilarity under the condition allow existence certain the crack of width.But at under construction should as far as possible adopt a valid measure control crack creation, make the structure don't appear crack possibly or as far as possible decrease crack of amount and width, particularly want to as far as possible avoid harmful crack of emergence, insure engineering quality thus. Concrete crack creation of the reason be a lot of and have already transformed to cause of crack:Such as temperature variety, constringency, inflation, the asymmetry sink to sink etc. reason cause of crack;Have outside carry the crack that the function cause;Protected environment not appropriate the crack etc. caused with chemical effect.Want differentiation to treat in the actual engineering, work°out a problem according to the actual circumstance. In the concrete engineering the familiar crack and the prevention 1.Stem Suo crack and prevention Stem the Suo crack much appear after the concrete protect be over of a period of time or concrete sprinkle to build to complete behind of around a week.In the cement syrup humidity of evaporate would creation stem Suo, and this kind of constringency is can't negative.Stem Suo crack of the creation be main is because of concrete inside outside humidity evaporate degree dissimilarity but cause to transform dissimilarity of result:The concrete is subjected to exterior condition of influence, surface humidity loss lead quick, transform bigger, inner part degree of humidity variety smaller transform smaller, bigger surface stem the Suo transform to be subjected to concrete inner part control, creation more big pullshould dint but creation crack.The relative humidity is more low, cement syrup body stem Suo more big, stem the Suo crack be more easy creation.Stem the Suo crack is much surface parallel lines form or the net shallow thin crack, width many between 0.05-0.2 mm, the flat surface part much see in the big physical volume concrete and follow it more in thinner beam plank short to distribute.Stem Suo crack usually the anti- Shen of influence concrete, cause the durable of the rust eclipse influence concrete of reinforcing bar, under the function of the water pressure dint would creation the water power split crack influence concrete of loading dint etc..Concrete stem the Suo be main with water ash of the concrete ratio, the dosage of the composition, cement of cement, gather to anticipate of the dosage of the property and dosage, in addition etc. relevant. Main prevention measure:While being to choose to use the constringency quantity smaller cement, general low hot water mire and powder ash from stove cement in the adoption, lower the dosage of cement.Two is a concrete of stem the Suo be subjected to water ash ratio of influence more big, water ash ratio more big, stem Suo more big, so in the concrete match the ratio the design should as far as possible control good water ash ratio of choose to use, the Chan add in the meantime accommodation of reduce water.Three is strict control concrete mix blend with under construction of match ratio, use of concrete water quantity absolute can't big in match ratio design give settle of use water quantity.Four is the earlier period which strengthen concrete to protect, and appropriate extension protect of concrete time.Winter construction want to be appropriate extension concrete heat preservation to overlay time, and Tu2 Shua protect to protect.Five is a constitution the accommodation is in the concrete structure of the constringency sew. 2.The Su constringency crack and prevention Su constringency is the concrete is before condense, surface because of lose water quicker but creation of constringency.The Su constringency crack is general at dry heat or strong wind the weather appear, crack's much presenting in the center breadth, both ends be in the centerthin and the length be different, with each other not coherent appearance.Shorter crack general long 20-30 cm, the longer crack can reach to a 2-3 m, breadth 1-5 mm.It creation of main reason is:The concrete is eventually almost having no strength or strength before the Ning very small, perhaps concrete just eventually Ning but strength very hour, be subjected to heat or compare strong wind dint of influence, the concrete surface lose water to lead quick, result in in the capillary creation bigger negative press but make a concrete physical volume sharply constringency, but at this time the strength of concrete again can't resist itsconstringency, therefore creation cracked.The influence concrete Su constringency open the main factor of crack to have water ash ratio, concrete of condense time, environment temperature, wind velocity, relative humidity……etc.. Main prevention measure:One is choose to use stem the Suo value smaller higher Huo sour salt of the earlier period strength or common the Huo sour brine mire.Two is strict the control water ash ratio, the Chan add to efficiently reduce water to increment the collapse of concrete fall a degree and with easy, decrease cement and water of dosage.Three is to sprinkle before building concrete, water basic level and template even to soak through.Four is in time to overlay the perhaps damp grass mat of the plastics thin film, hemp slice etc., keep concrete eventually before the Ning surface is moist, perhaps spray to protect etc. to carry on protect in the concrete surface.Five is in the heat and strong wind the weather to want to establish to hide sun and block breeze facilities, protect in time. 3.Sink to sink crack and prevention The creation which sink to sink crack is because of the structure foundation soil quality not and evenly, loose soft or return to fill soil dishonest or soak in water but result in theasymmetry sink to decline with the result that;Perhaps because of template just degree shortage, the template propped up to once be apart from big or prop up bottom loose move etc. to cause, especially at winter, the template prop up at jelly soil up, jelly the soil turn jelly empress creation asymmetry to sink to decline and cause concrete structure creation crack.This kind crack many is deep enter or pierce through sex crack, it alignment have something to do with sinking to sink a circumstance, general follow with ground perpendicular or present 30 °s-45 °Cape direction development, bigger sink to sink crack, usually have certain of wrong, crack width usually with sink to decline quantity direct proportion relation.Crack width under the influence of temperature variety smaller.The foundation after transform stability sink to sink crack also basic tend in stability. Main prevention measure:One is rightness loose soft soil, return to fill soil foundation a construction at the upper part structure front should carry on necessity of Hang solid with reinforce.Two is the strength that assurance template is enough andjust degree, and prop up firm, and make the foundation be subjected to dint even.Three is keep concrete from sprinkle infusing the foundation in the process is soak by water.Four is time that template tore down to can't be too early, and want to notice to dismantle a mold order of sequence.Five is at jelly soil top take to establish template to notice to adopt certain of prevention measure. 4.Temperature crack and prevention Temperature crack much the occurrence is in big surface or difference in temperature variety of the physical volume concrete compare the earth area of the concrete structure.Concrete after sprinkling to build, in the hardening the process, cement water turn a creation a great deal of of water turn hot, .(be the cement dosage is in the 350-550 kg/m 3, each sign square the rice concrete will release a calories of 17500-27500 kJ and make concrete internal thus the temperature rise to reach to 70 ℃or so even higher)Because the physical volume of concrete be more big, a great deal of of water turn hot accumulate at the concrete inner part but not easy send forth, cause inner part the temperature hoick, but the concrete surface spread hot more quick, so formation inside outside of bigger difference in temperature, the bigger difference in temperature result in inner part and exterior hot the degree of the bulge cold Suo dissimilarity, make concrete surface creation certain of pull should dint.When pull should dint exceed the anti- of concrete pull strength extreme limit, concrete surface meeting creation crack, this kind of crack much occurrence after the concrete under construction period.In the concrete of under construction be difference in temperature variety more big, perhaps is a concrete to be subjected to assault of cold wave etc., will cause concrete surface the temperature sharply descend, but creation constringency, surface constringency of the concrete be subjected to inner part concrete of control, creation very big of pull should dint but creation crack, this kind of crack usually just in more shallow scope of the concrete surface creation. The alignment of the temperature crack usually none settle regulation, big area structure the crack often maneuver interleave;The size bigger structure of the beam plank length, the crack run parallel with short side more;Thorough with pierce through sex of temperature crack general and short side direction parallelism or closeparallelism, crack along long side cent the segment appear, in the center more airtight.Crack width the size be different, be subjected to temperature variety influence more obvious, winter compare breadth, summer more narrow.The concrete temperature crack that the heat inflation cause is usually in the center the thick both ends be thin, but cold Suo crack of thick thin variety not too obvious.The emergence of the this kind crack will cause the rust eclipse of reinforcing bar, the carbonization of concrete, the anti- jelly which lower concrete melt, anti- tired and anti- Shenability etc.. Main prevention measure:One is as far as possible choose to use low hot or medium hot water mire, like mineral residue cement, powder ash from stove cement……etc..Two is a decrease cement dosage, cement dosage as far as possible the control is in the 450 kg/m 3 following.Three is to lower water ash ratio, water ash of the general concrete ratio control below 0.6.Four is improvement the bone anticipate class to go together with, the Chan add powder ash from stove or efficiently reduce water etc. to come to reduce cement dosage and lower water to turn hot.Five is an improvement concrete of mix blend to process a craft, lower sprinkle of concrete to build temperature.Six is the in addition that the Chan add a have of fixed amount to reduce water and increase Su, slow Ning etc. function in the concrete, improvement the concrete mix to match a thing of mobility, protect water, lower water to turn hot, postpone hot Feng of emergence time.Seven is the heat season sprinkle to build can the adoption take to establish to hide sun plank etc. assistance measure control concrete of Wen Sheng, lowBuilding construction concrete crack of prevention and processingAbstractThe crack problem of concrete is a widespread existence but again difficult in solve of engineering actual problem, this text carried on a study analysis to a little bit familiar crack problem in the concrete engineering, and aim at concrete the circumstance put forward some prevention, processing measure. Keyword:Concrete crack prevention processing ForewordConcrete's ising 1 kind is anticipate by the freestone bone, cement, water and other mixture but formation of the in addition material of quality brittleness not and all material.Because the concrete construction transform with oneself, control etc. a series problem, harden model of in the concrete existence numerous tiny hole, spirit cave and tiny crack, is exactly because these beginning start blemish of existence just make the concrete present one some not and all the characteristic of quality.The tiny crack is a kind of harmless crack and accept concrete heavy, defend Shen and a little bit other use function not a creation to endanger.But after the concrete be subjected to lotus carry, difference in temperature etc. function, tiny crack would continuously of expand with connect, end formation we can see without the aid of instruments of macro view the crack be also the crack that the concrete often say in the engineering. Concrete building and Gou piece usually all take sewer to make of, because of crack of existence and development usually make inner part of reinforcing bar etc. material creation decay, lower reinforced concrete material of loading ability, durable and antiShen ability, influence building of external appearance, service life, severity will threat arrive people's life and property safety.A lot of all of crash of engineerings is because of the unsteady development of the crack with the result that.Modern age science research with a great deal of of the concrete engineering practice certificate, in the concrete engineering crack problem is ineluctable, also acceptable in certainly of the scope just need to adopt valid of measure will it endanger degree control at certain of scope inside.The reinforced concrete norm is also explicit provision:Some structure at place of dissimilarity under the condition allow existence certain the crack of width.But at under construction should as far as possible adopt a valid measure control crack creation, make the structure don't appear crack possibly or as far as possible decrease crack of amount and width, particularly want to as far as possible avoid harmful crack of emergence, insure engineering quality thus. Concrete crack creation of the reason be a lot of and have already transformed to cause of crack:Such as temperature variety, constringency, inflation, the asymmetry sink to sink etc. reason cause ofcrack;Have outside carry the crack that the function cause;Protected environment not appropriate the crack etc. caused with chemical effect.Want differentiation to treat in the actual engineering, work°out a problem according to the actual circumstance. In the concrete engineering the familiar crack and the prevention 1.Stem Suo crack and prevention Stem the Suo crack much appear after the concrete protect be over of a period of time or concrete sprinkle to build to complete behind of around a week.In the cement syrup humidity of evaporate would creation stem Suo, and this kind of constringency is can't negative.Stem Suo crack of the creation be main is because of concrete inside outside humidity evaporate degree dissimilarity but cause to transform dissimilarity of result:The concrete is subjected to exterior condition of influence, surface humidity loss lead quick, transform bigger, inner part degree of humidity variety smaller transform smaller, bigger surface stem the Suo transform to be subjected to concrete inner part control, creation more big pull should dint but creation crack.The relative humidity is more low, cement syrup body stem Suo more big, stem the Suo crack be more easy creation.Stem the Suo crack is much surface parallel lines form or the net shallow thin crack, width many between 0.05-0.2 mm, the flat surface part much see in the big physical volume concrete and follow it more in thinner beam plank short to distribute.Stem Suo crack usually the anti- Shen of influence concrete, cause the durable of the rust eclipse influence concrete of reinforcing bar, under the function of the water pressure dint would creation the water power split crack influence concrete of loading dint etc..Concrete stem the Suo be main with water ash of the concrete ratio, the dosage of the composition, cement of cement, gather to anticipate of the dosage of the property and dosage, in addition etc. relevant. Main prevention measure:While being to choose to use the constringency quantity smaller cement, general low hot water mire and powder ash from stove cement in the adoption, lower the dosage of cement.Two is a concrete of stem the Suo be subjected to water ash ratio of influence more big, water ash ratio more big, stem Suo more big, so in the concrete match the ratio the design should as far as possible control good water ash ratio of choose to use, the Chan add in the meantime accommodation of reduce water.Three is strict control concrete mix blend with under construction of match ratio, use of concrete water quantity absolute can't big in match ratio design give settle of use water quantity.Four is the earlier period which strengthen concrete to protect, and appropriate extension protect of concrete time.Winter construction want to be appropriate extension concrete heat preservation to overlay time, and Tu2 Shua protect to protect.Five is a constitution the accommodation is in the concrete structure of the constringency sew. 2.The Su constringency crack and prevention Su constringency is the concrete is before condense, surface because of lose water quicker but creation of constringency.The Su constringency crack is general at dry heat or strong wind the weather appear, crack's much presenting in the center breadth, both ends be in the centerthin and the length be different, with each other not coherent appearance.Shorter crack general long 20-30 cm, the longer crack can reach to a 2-3 m, breadth 1-5 mm.It creation of main reason is:The concrete is eventually almost having no strength or strength before the Ning very small, perhaps concrete just eventually Ning but strength very hour, be subjected to heat or compare strong wind dint of influence, the concrete surface lose water to lead quick, result in in the capillary creation bigger negative press but make a concrete physical volume sharply constringency, but at this time the strength of concrete again can't resist itsconstringency, therefore creation cracked.The influence concrete Su constringency open the main factor of crack to have water ash ratio, concrete of condense time, environment temperature,wind velocity, rela tive humidity……etc.. Main prevention measure:One is choose to use stem the Suo value smaller higher Huo sour salt of the earlier period strength or common the Huo sour brine mire.Two is strict the control water ash ratio, the Chan add to efficiently reduce water to increment the collapse of concrete fall a degree and with easy, decrease cement and water of dosage.Three is to sprinkle before building concrete, water basic level and template even to soak through.Four is in time to overlay the perhaps damp grass mat of the plastics thin film, hemp slice etc., keep concrete eventually before the Ning surface is moist, perhaps spray to protect etc. to carry on protect in the concrete surface.Five is in the heat and strong wind the weather to want to establish to hide sun and block breeze facilities, protect in time. 3.Sink to sink crack and prevention The creation which sink to sink crack is because of the structure foundation soil quality not and evenly, loose soft or return to fill soil dishonest or soak in water but result in the asymmetry sink to decline with the result that;Perhaps because of template just degree shortage, the template propped up to once be apart from big or prop up bottom loose move etc. to cause, especially at winter, the template prop up at jelly soil up, jelly the soil turn jelly empress creation asymmetry to sink to decline and cause concrete structure creation crack.This kind crack many is deep enter or pierce through sex crack, it alignment have something to do with sinking to sink a circumstance, general follow with ground perpendicular or present 30 °s-45 °Cape direction development, bigger sink to sink crack, usually have certain of wrong, crack width usually with sink to decline quantity direct proportion relation.Crack width under the influence of temperature variety smaller.The foundation after transform stability sink to sink crack also basic tend in stability. Main prevention measure:One is rightness loose soft soil, return to fill soil foundation a construction at the upper part structure front should carry on necessity of Hang solid with reinforce.Two is the strength that assurance template is enough andjust degree, and prop up firm, and make the foundation be subjected to dint even.Three is keep concrete from sprinkle infusing the foundation in the process is soak by water.Four is time that template tore down to can't be too early, and want to notice to dismantle a mold order of sequence.Five is at jelly soil top take to establish template to notice to adopt certain of prevention measure. 4.Temperature crack and prevention Temperature crack much the occurrence is in big surface or difference in temperature variety of the physical volume concrete compare the earth area of the concrete structure.Concrete after sprinkling to build, in the hardening the process, cement water turn a creation a great deal of of water turn hot, .(be the cement dosage is in the 350-550 kg/m 3, each sign square the rice concrete will release a calories of 17500-27500 kJ and make concrete internal thus the temperature rise to reach to 70 ℃or so even higher)Because the physical volume of concrete be more big, a great deal of of water turn hot accumulate at the concrete inner part but not easy send forth, cause inner part the temperature hoick, but the concrete surface spread hot more quick, so formation inside outside of bigger difference in temperature, the bigger difference in temperature result in inner part and exterior hot the degree of the bulge cold Suo dissimilarity, make concrete surface creation certain of pull should dint.When pull should dint exceed the anti- of concrete pull strength extreme limit, concrete surface meeting creation crack, this kind of crack much occurrence after the concrete under construction period.In the concrete of under construction be difference in temperature variety more big, perhaps is a concrete to be subjected to assault of cold wave etc., will cause concrete surface the temperature sharply descend, but creation constringency, surface constringency of the concrete be subjected to inner part concrete of control, creation very big of pull should dint but creation crack, this kind of crackusually just in more shallow scope of the concrete surface creation. The alignment of the temperature crack usually none settle regulation, big area structure the crack often maneuver interleave;The size bigger structure of the beam plank length, the crack run parallel with short side more;Thorough with pierce through sex of temperature crack general and short side direction parallelism or closeparallelism, crack along long side cent the segment appear, in the center more airtight.Crack width the size be different, be subjected to temperature variety influence more obvious, winter compare breadth, summer more narrow.The concrete temperature crack that the heat inflation cause is usually in the center the thick both ends be thin, but cold Suo crack of thick thin variety not too obvious.The emergence of the this kind crack will cause the rust eclipse of reinforcing bar, the carbonization of concrete, the anti- jelly which lower concrete melt, anti- tired and anti- Shen ability etc.. Main prevention measure:One is as far as possible choose to use low hot or medium hot water mire, like mineral residue cement, powder ash from stove cement……etc..Two is a decrease cement dosage, cement dosage as far as possible the control is in the 450 kg/m 3 following.Three is to lower water ash ratio, water ash of the general concrete ratio control below 0.6.Four is improvement the bone anticipate class to go together with, the Chan add powder ash from stove or efficiently reduce water etc. to come to reduce cement dosage and lower water to turn hot.Five is an improvement concrete of mix blend to process a craft, lower sprinkle of concrete to build temperature.Six is the in addition that the Chan add a have of fixed amount to reduce water and increase Su, slow Ning etc. function in the concrete, improvement the concrete mix to match a thing of mobility, protect water, lower water to turn hot, postpone hot Feng of emergence time.Seven is the heat season sprinkle to build can the adoption take to establish to hide sun plank etc. assistance measure control concrete of Wen Sheng, lower to sprinkle temperature of build the concrete.Eight is the temperature of big physical volume concrete should the dint relate to structure size, concrete structure size more big, temperature should dint more big, so want reasonable arrangement construction work preface, layering, cent the piece sprinkle to build, for the convenience of in spread hot, let up control.Nine is at great inner part constitution of the physical volume concrete cool off piping, cold water perhaps cold air cool off, let up concrete of inside outside difference in temperature.Ten is the supervision which strengthen concrete temperature, adopt to cool off in time, protection measure.11 is to reserve temperature constringency to sew.12 is to let up to control, sprinkle proper before building concrete in the Ji rock and old concrete top build a 5 mm or so sand mat a layer or usage asphalt etc. material Tu2 Shua.13 is to strengthen concrete to protect, the concrete after sprinkle build use moist grass Lian in time, hemp slice's etc. overlay, and attention sprinkle water to protect, appropriate extension protect time, assurance the concrete surface be slow-moving cool off.At the cold season, concrete surface should constitution heat preservation measure, in order to prevent cold wave assault.14 is the allocation be a little amount in the concrete of reinforcing bar perhaps add fiber material concrete of temperature crack control at certain of scope inside. 5.Crack and prevention that the chemical reaction cause Alkali bone's anticipating the crack that reaction crack and reinforcing bar rust eclipse cause is the most familiar in the reinforced concrete structure of because of chemical reaction but cause of crack. The concrete blend a future reunion creation some alkalescence ion, these ion with some activity the bone anticipate creation chemical reaction and absorb surroundings environment in of water but the physical volume enlarge, make concrete crisp loose, inflation open crack.In this kind of crack general emergence concrete structure usage。
土木工程专业外文翻译--土木工程
外文原文：Civil EngineeringCivil engineering is the planning, design, construction, and management of the built environment. This environment includes all structures built according to scientific principles, from irrigation and drainage systems to rocket launching facilities.Civil engineers build roads, bridges, tunnels, dams, harbors, power plants, water and sewage systems, hospitals, schools, mass transit, and other public facilities essential to modern society and large population concentrations. They also build privately owned facilities such as airport, railroads, pipelines, skyscrapers, and other large structures designed for industrial, commercial, or residential use. In addition, civil engineers plan, design, and build complete cities and towns, and more recently have been planning and designing space platforms to self-contained communities.The word civil derives from the Latin for citizen. In 1782, Englishman John Seaton used the term to differentiate his nonmilitary engineering work from that of the military engineers who predominated at the time. Since then, the term civil engineer has often been used to refer to engineers who build public facilities, although the field is much broader.Scope Because it is so broad, civil engineering is subdivided into a number of technical specialties. Depending on the type of project, the skills pf many kinds of civil engineer specialties may be needed. When a project begins, the site is surveyed and mapped by civil engineers who experiment to determine if the earth can bear the weight of project. Environmental specialists study the project’s impact on the local area, the potential for air and groundwater pollution, the project’s impact on local animal and plant life, and how the project can be designed to meet government requirements aimed at protecting the environment. Transportation specialists determine what kind of facilities are needed to ease the burden on local roads and other transportation networks that will result from the completed project. Meanwhile, structural specialists raise preliminary data to make detailed designs, plans, and specifications for the project. Supervising and coordinating the work of these civil engineer specialists, from beginning to end of the project, are the construction management specialists. Based on information supplied by the other specialists, construction management civil engineers estimate quantitiesand costs of materials and subcontractors, and perform other supervisory work to ensure the project is completed on time and as specified.Many civil engineers, among them the top people in the field, work in design. As we have seen, civil engineers work on many different kinds of structures, so it is normal practice for an engineer to specialize in just one kind. In designing buildings, engineers often work as consultants to architectural or construction firms. Dams, bridges, water supply systems, and other large projects ordinarily employ several engineers whose work is coordinated by a system engineer who is in charge of the entire project. In many cases, engineers from other disciplines are involved. In a dam project, for example, electrical and mechanical engineers work on the design of the powerhouse and its equipment. In other cases, civil engineers are assigned to work on a project in another field; in the space program, for instance, civil engineers were necessary in the design and construction of such structures as launching pads and rocket storage facilities.Throughout any given project, civil engineers make extensive use of computers. Computes are used to design the project’s various elements (computer-aided design, or CAD) and to manger it. Computers are a necessity for the modern civil engineer because they permit the engineer to efficiently handle the large quantities of data needed in determining the best way to construct a project.Structural engineering In this specialty, civil engineers plan and design structures of all types, including bridges dams, power plants, supports for equipment, special structures for offshore projects, the United States space program, transmission towers, giant astronomical and radio telescopes, and many other kinds of projects.Using computers, structural engineers determine the forces a structure must resist, its own weight, wind and hurricane forces temperature changes that expand or contract construction materials, and earthquakes. They also determine the combination of appropriate materials: steel, concrete, plastic, stone, asphalt, brick, aluminum, or other construction materials.Water resources engineering Civil engineers in this specialty deal with all aspects of the physical control of water. Their projects help prevent floods, supply water for cities and for irrigation, manage and control rivers and water runoff, and maintain beaches and other waterfront facilities. In addition, they design and maintain harbors, canals, and locks, build huge hydroelectric dams and smaller dams and water impoundments of all kinds, help design offshorestructures, and determine the location of structures affecting navigation.Geotechnical engineering Civil engineers who specialize in this filed analyze the properties of soils and rocks that support structures and affect structural behavior. They evaluate and work to minimize the potential settlement of buildings and other structures that stems from the pressure of their weight on the earth. These engineers also evaluate and determine how to strengthen the stability of slopes and how to protect structures against earthquakes and the effects of groundwater.Environmental engineering In this branch of engineering, civil engineers design, build, and supervise systems to provide safe drinking water and to prevent and control pollution of water supplies, both on the surface and underground. They also design, build, and supervise projects to control or eliminate pollution of the land and air. These engineers build water and wastewaters treatment plants, and design air scrubbers and other devices to minimize or eliminate air pollution caused by industrial processes, incineration, or other smoke-producing activities. They also work to control toxic and hazardous wastes through the construction of special dump sites or the neutralizing of toxic and hazardous substances. In addition the engineers design and manage sanitary landfills to prevent pollution of surrounding land.Transportation engineering Civil engineers working in this specialty build facilities to ensure safe and efficient movement of both people and goods. They specialize in designing and maintaining all types of transportation facilities, highways and streets, mass transit systems, railroads and airfields ports and harbors. Transportation engineers apply technological knowledge as well as consideration of the economic, political, and social factors in designing each project. They work closely with urban planners since the quality of the community is directly related to the quality of the transportation system.Pipeline engineering In this branch of civil engineering, engineers build pipelines and related facilities, which transport liquids, gases, or solids ranging from coal slurries (mixed coal and water) and semi liquids wastes, to water, oil and various types pf highly combustible and noncombustible gases. The engineers determine pipeline design, the economic and environmental impact of a project on regions it must traverse, the type pf materials to be used-steel, concrete, plastic, or combinations of various materials, installation techniques, methods for testing pipeline strength, and controls for maintaining proper pressure and rate of flow of materials being transported. When hazardous materials are being carried, safety is a major consideration as well.Construction engineering Civil engineers in this field oversee the construction of a project from beginning to end. Sometimes called project engineers, they apply both technical and managerial skills, including knowledge of construction methods, planning, organizing, financing, and operating construction projects. They coordinate the activities of virtually everyone engaged in the work: the surveyors, workers who lay out and construct the temporary roads and ramps, excavate for the foundation, build the forms and pour the concrete; and workers who build the steel frame-work. These engineers also make regular progress reports to the owners of the structure.Construction is a complicated process on almost all engineering projects. It involves scheduling the work and utilizing the equipment and the materials so that coats are kept as low as possible. Safety factor must also be taken into account, since construction can be very dangerous. Many civil engineers therefore specialize in the construction phase.Community and urban planning Those engaged in this area of civil engineering may plan and develop communities within a city, or entire cities. Such planning involves far more than engineering considerations; environmental, social, and economic factors in the use and development of land and natural resources are also key elements. They evaluate the kinds of facilities needed, including streets and highways, public transportation systems, airports, and recreational and other facilities to ensure social and economic as well as environmental well-being.Photogrammetry, surveying, and mapping The civil engineers in this specialty precisely measure the Earth’s surface to obtain reliable information for locating and designing engineering projects. This practice often involves high-technology methods such as satellite and aerial surveying, and computer processing of photographic imagery. Radio signals from satellites, scanned by laser and sonic beams, are converted to maps to provide very accurate measurements for boring tunnels, building highways and dams, plotting flood control and irrigation projects, locating subsurface geologic formations that may affect a construction project and a host of other building uses.Other specialties Three additional civil engineering specialties that are not entirely within the scope of civil engineering teaching.Engineering research Research is one of the most important aspects of scientific and engineering practice. A researcher usually works as a member of a team with other scientists and engineers. He or she is often employed in alaboratory that financed by government or industry. Areas of research connected with civil engineering include soil mechanics and soil stabilization techniques, and also the development and testing of new structural materials.Engineering management Many civil engineers choose careers that eventually lead to management. Others are also to start their careers in management positions. The civil engineer manager combines technical knowledge with an ability to organize and coordinate worker power, materials, machinery, and money. These engineers may work in government municipal, county, state, or federal; in the U.S.Army Corps of Engineers as military or civilian management engineers; or in semiautonomous regional or city authorities or similar organization. They may also manage private engineering firms ranging in size from a few employees to hundreds.Engineering teaching The civil engineer who chooses a teaching career usually teaches both graduate and undergraduate students in technical specialties. Many teaching civil engineers engage in basic research that eventually leads to technical innovations in construction materials and methods. Many also serve as consultants on engineering projects, or on technical boards and commissions associated with major projects.中文译文：土木工程土木工程是指对建成环境的规划、设计、建造、管理等一系列活动。
土木工程 外文翻译 外文文献 英文文献
一、外文原文Talling building and Steel construction Although there have been many advancements in building construction technology in general. Spectacular archievements have been made in the design and construction of ultrahigh-rise buildings.The early development of high-rise buildings began with structural steel framing.Reinforced concrete and stressed-skin tube systems have since been economically and competitively used in a number of structures for both residential and commercial purposes.The high-rise buildings ranging from 50 to 110 stories that are being built all over the United States are the result of innovations and development of new structual systems.Greater height entails increased column and beam sizes to make buildings more rigid so that under wind load they will not sway beyond an acceptable limit.Excessive lateral sway may cause serious recurring damage to partitions,ceilings.and other architectural details. In addition,excessive sway may cause discomfort to the occupants of the building because their perception of such motion.Structural systems of reinforced concrete,as well as steel,take full advantage of inherent potential stiffness of the total building and therefore require additional stiffening to limit the sway.In a steel structure,for example,the economy can be defined in terms of the total average quantity of steel per square foot of floor area of the building.Curve A in Fig .1 represents the average unit weight of a conventional frame with increasing numbers of stories. Curve B represents the average steel weight if the frame is protected from all lateral loads. The gap between the upper boundary and the lower boundary represents the premium for height for the traditional column-and-beam frame.Structural engineers have developed structural systems with a view to eliminating this premium.Systems in steel. Tall buildings in steel developed as a result ofseveral types of structural innovations. The innovations have been applied to the construction of both office and apartment buildings.Frame with rigid belt trusses. In order to tie the exterior columns of a frame structure to the interior vertical trusses,a system of rigid belt trusses at mid-height and at the top of the building may be used. A good example of this system is the First Wisconsin Bank Building(1974) in Milwaukee.Framed tube. The maximum efficiency of the total structure of a tall building, for both strength and stiffness,to resist wind load can be achieved only if all column element can be connected to each other in such a way that the entire building acts as a hollow tube or rigid box in projecting out of the ground. This particular structural system was probably used for the first time in the 43-story reinforced concrete DeWitt Chestnut Apartment Building in Chicago. The most significant use of this system is in the twin structural steel towers of the 110-story World Trade Center building in New York Column-diagonal truss tube. The exterior columns of a building can be spaced reasonably far apart and yet be made to work together as a tube by connecting them with diagonal members interesting at the centre line of the columns and beams. This simple yet extremely efficient system was used for the first time on the John Hancock Centre in Chicago, using as much steel as is normally needed for a traditional 40-story building.Bundled tube. With the continuing need for larger and taller buildings, the framed tube or the column-diagonal truss tube may be used in a bundled form to create larger tube envelopes while maintaining high efficiency. The 110-story Sears Roebuck Headquarters Building in Chicago has nine tube, bundled at the base of the building in three rows. Some of these individual tubes terminate at different heights of the building, demonstrating the unlimited architectural possibilities of this latest structural concept. The Sears tower, at a height of 1450 ft(442m), is the world’s tallest building.Stressed-skin tube system. The tube structural system was developed for improving the resistance to lateral forces (wind and earthquake) and thecontrol of drift (lateral building movement ) in high-rise building. The stressed-skin tube takes the tube system a step further. The development of the stressed-skin tube utilizes the façade of the building as a structural element which acts with the framed tube, thus providing an efficient way of resisting lateral loads in high-rise buildings, and resulting in cost-effective column-free interior space with a high ratio of net to gross floor area.Because of the contribution of the stressed-skin façade, the framed members of the tube require less mass, and are thus lighter and less expensive. All the typical columns and spandrel beams are standard rolled shapes,minimizing the use and cost of special built-up members. The depth requirement for the perimeter spandrel beams is also reduced, and the need for upset beams above floors, which would encroach on valuable space, is minimized. The structural system has been used on the 54-story One Mellon Bank Center in Pittburgh.Systems in concrete. While tall buildings constructed of steel had an early start, development of tall buildings of reinforced concrete progressed at a fast enough rate to provide a competitive chanllenge to structural steel systems for both office and apartment buildings.Framed tube. As discussed above, the first framed tube concept for tall buildings was used for the 43-story DeWitt Chestnut Apartment Building. In this building ,exterior columns were spaced at 5.5ft (1.68m) centers, and interior columns were used as needed to support the 8-in . -thick (20-m) flat-plate concrete slabs.Tube in tube. Another system in reinforced concrete for office buildings combines the traditional shear wall construction with an exterior framed tube. The system consists of an outer framed tube of very closely spaced columns and an interior rigid shear wall tube enclosing the central service area. The system known as the tube-in-tube system , made it possible to design the world’s present tallest (714ft or 218m)lightweight concrete bu ilding( the 52-story One Shell Plaza Building in Houston) for the unit price of a traditional shear wall structure of only 35 stories.Systems combining both concrete and steel have also been developed, an examle of which is the composite system developed by skidmore, Owings &Merril in which an exterior closely spaced framed tube in concrete envelops an interior steel framing, thereby combining the advantages of both reinforced concrete and structural steel systems. The 52-story One Shell Square Building in New Orleans is based on this system.Steel construction refers to a broad range of building construction in which steel plays the leading role. Most steel construction consists of large-scale buildings or engineering works, with the steel generally in the form of beams, girders, bars, plates, and other members shaped through the hot-rolled process. Despite the increased use of other materials, steel construction remained a major outlet for the steel industries of the U.S, U.K, U.S.S.R, Japan, West German, France, and other steel producers in the 1970s.二、原文翻译高层结构与钢结构近年来，尽管一般的建筑结构设计取得了很大的进步，但是取得显著成绩的还要属超高层建筑结构设计。
土木工程--外文文献翻译
土木工程--外文文献翻译-CAL-FENGHAI.-(YICAI)-Company One1学院：专业：土木工程姓名：学号：外文出处： Structural Systems to resist (用外文写)Lateral loads附件： 1.外文资料翻译译文；2.外文原文。
附件1：外文资料翻译译文抗侧向荷载的结构体系常用的结构体系若已测出荷载量达数千万磅重，那么在高层建筑设计中就没有多少可以进行极其复杂的构思余地了。
确实，较好的高层建筑普遍具有构思简单、表现明晰的特点。
这并不是说没有进行宏观构思的余地。
实际上，正是因为有了这种宏观的构思，新奇的高层建筑体系才得以发展，可能更重要的是：几年以前才出现的一些新概念在今天的技术中已经变得平常了。
如果忽略一些与建筑材料密切相关的概念不谈，高层建筑里最为常用的结构体系便可分为如下几类：1.抗弯矩框架。
2.支撑框架，包括偏心支撑框架。
3.剪力墙，包括钢板剪力墙。
4.筒中框架。
5.筒中筒结构。
6.核心交互结构。
7. 框格体系或束筒体系。
特别是由于最近趋向于更复杂的建筑形式，同时也需要增加刚度以抵抗几力和地震力，大多数高层建筑都具有由框架、支撑构架、剪力墙和相关体系相结合而构成的体系。
而且，就较高的建筑物而言，大多数都是由交互式构件组成三维陈列。
将这些构件结合起来的方法正是高层建筑设计方法的本质。
其结合方式需要在考虑环境、功能和费用后再发展，以便提供促使建筑发展达到新高度的有效结构。
这并不是说富于想象力的结构设计就能够创造出伟大建筑。
正相反，有许多例优美的建筑仅得到结构工程师适当的支持就被创造出来了，然而，如果没有天赋甚厚的建筑师的创造力的指导，那么，得以发展的就只能是好的结构，并非是伟大的建筑。
无论如何，要想创造出高层建筑真正非凡的设计，两者都需要最好的。
虽然在文献中通常可以见到有关这七种体系的全面性讨论，但是在这里还值得进一步讨论。
设计方法的本质贯穿于整个讨论。
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本科毕业设计（论文）外文翻译译文学生姓名：院（系）：专业班级：指导教师：完成日期：钢筋混凝土填充框架结构对拆除两个相邻的柱的响应作者：Mehrdad Sasani 美国波士顿东北大学，斯奈尔400设计中心MA02115收稿日期：2007年7月27日，修整后收稿日期2007年12月26日，录用日期2008年1月24日，网上上传日期2008年3月19日。
摘要：本文是评价圣地亚哥旅馆对同时拆除两根相邻的外柱的响应问题，圣地亚哥旅馆是个6层钢筋混凝土填充框架结构。
结构的分析模型应用了有限元法和以此为基础的分析模型来计算结构的整体和局部变形。
分析结果跟实验结果非常吻合。
当测量的竖向位移增加到为四分之一英寸（即6.4mm）的时候，结构就发生连续倒塌。
通过实验分析方法评价和讨论随着柱的移除而产生的变形沿着结构高度上的发展和荷载动态重分配。
讨论了轴向和弯曲的变形传播的不同。
结构横向和纵向的三维桁架在填充墙的参与下被认为是荷载重分配的主要构件。
讨论了两种潜在的脆性破坏模型（没有拉力加强的梁的脆断和有加筋肋的梁的挤出）。
分析评价了结构对额外的重力和无填充墙时的响应。
Elsevier有限责任公司对此文保留所有权利。
关键词：连续倒塌；荷载重分配；对荷载抵抗能力；动态响应；非线性分析；脆性破坏。
1. 介绍：作为减小由于结构的局部损坏而造成大量伤亡的可能性措施的一部分，美国总务管理局【1】和国防部【2】出台了一系列制度来评价结构对连续倒塌的抵抗力。
【3】定义连续倒塌为，由原始单元的局部破坏在单元间的扩展最终造成结构的整体或不成比例的大部破坏。
通过Ellingwood 和Leyendecker【4】建议的方法，ASCE/SEI 7定义了两种一般模型来减小结构设计时连续倒塌效应产生的损害，它们分为直接和间接的设计方法。
一般建筑规范和标准用增加结构的整体性的间接设计方法。
间接设计法也应用于美国国防部的降低连续倒塌设计和未归档设备标准中。
尽管间接设计法可以降低连续破坏的风险【6，7】，对基于此法设计的结构破坏后的表现的判断是不容易实现的。
有一种基于直接设计的方法通过研究瞬间消除受载构件，比如柱子，对结构的影响来评价结构的连续倒塌。
美国防部和国家事务管理局的规章是要求去除一个受荷构件，考虑其影响。
这样的规范目的是评价结构的整体性和结构的一个单元出现严重的毁坏时的分荷能力。
这种方法是研究结构受连续倒塌的影响的程度，但是事实上初始结构损伤的影响不止局限于某一根柱子。
在本论文中，应用通过实验证实的分析结果，评价圣地亚哥旅馆抵抗连续破坏的能力，实验中瞬间移除两个相邻的柱子，其中一个柱是拐角柱。
为了爆除这两个柱子，将炸药放在预先在柱子上钻的孔里面。
柱子然后再用几层保护材料包裹好，以避免爆炸时的冲击波和碎片影响结构的其他部分。
2. 建筑的特性圣地亚哥旅馆建造于1914年，在1924年又向南扩展了一部分，此部分包括两个分离的结构。
图.1是从南边看旅馆的样子。
注意这张照片，旅馆的第一和第三层被用黑色的布蒙了起来。
这个六层的旅馆是无延性的钢筋混凝土框架结构，其中还有由空心砖构成的填充外墙。
扩展部分的填充墙有两层共203mm厚。
第一层的楼高为6.0m，其他楼盖高为3.2m，顶楼高度为5.13m。
图.2为其中一个扩展部分的第二层。
图.3为对本建筑的实施计划，即瞬间爆除一层相邻的柱A2和A3，以评价其影响。
左图：图.1 圣地亚哥旅馆的南端视角，本论文研究其中心结构右图：图.2 扩展结构的第二层（南端视角）下图：图.3 拟对旅馆南扩展部分实施的柱的移除计划，第一层要被移除的柱用叉号标出如图.3所示楼盖系统纵向（南北向）有一个托梁。
根据两个混凝土构件受压的实验结果，对一个标准的混凝土柱，受压承载力为31MPa。
混凝土的弹性模量大概为26300MPa左右。
同样，通过横截面12.7mm的钢筋受拉实验，其屈服和极限抗拉强度分别为427和600MPa。
钢筋的极限变形为0.17。
钢筋的弹性模量近似为200000MPa。
这个建筑按计划将被爆破摧毁。
作为摧毁的一个步骤，第一层和第三层的填充墙被移除。
移除时上面没有活荷载。
所有的非结构部件包括隔墙、管道设备、家具都被事先搬走了，只有梁、柱、楼板梁和在边梁上的填充墙被留下。
3. 传感器布置混凝土和钢筋的应变传感器是用来测量梁和柱的应变变化的。
线性电位计用来测量整体和局部变形。
混凝土应变测量仪常900mm，最大应变为±0.02.钢筋应变测量仪应变极限为±0.2。
应变测量仪可以带到几百千赫兹。
电位计用来测量建筑中梁沿一端的转动和整体位移，这些以后将讲到。
电位计的分辨率为0.01mm，最大速度为1.0m/s，实验中最大记录速度为0.35m/s。
4. 有限元模型通过有限单元法，在软件SAP2000【8】中生成一个建筑模型。
梁和柱都被抽象成Bernoulli单元。
T和L型梁的翼缘计算宽度为四倍的较厚板的厚度【5】。
塑性铰可以发生在任何钢筋可能发生屈服的地方，包括单元的端点、加筋肋分离点和弯矩的屈服点。
在分析中，塑性铰的范围是构件高度的一半。
现行版本的SAP2000不能计算出单元斜裂缝的构成。
为了得出正确的构件挠曲刚度，反复做以下步骤：首先假设建筑的所有单元都是没有裂缝的；然后，需要弯矩同构件的出现裂缝的弯矩相比较。
分别降低板厚和梁的惯性矩35%，使需求弯矩大于裂缝出现弯矩。
梁外部出现裂缝的正负弯矩分别为58.2knM和37.9knM。
需要注意的是柱子没有裂缝出现。
再后，再按以上方法重新分析建筑和弯矩简图。
重复这些步骤直到所有的裂缝区域被鉴定和用模型表示出来。
除了两端区域建筑结构里的梁上部不配筋（图.4）。
例如，梁A1-A2在距A1点305mm以后，其上部不配筋（如图.4和5）。
为了确定出可能丧失挠曲强度的截面位置，将裂纹铰布置在上部没有配筋的可能的弯曲破坏点上。
塑性铰的挠曲强度设为于Mcr相等，当所受的弯矩达到Mcr时，该截面即发生破坏。
图.4 二层的梁A3-B3和梁A1-A2详细配筋情况楼盖系统有沿纵向（南北向）的次梁。
图.6所示为一典型的楼盖的横截面。
为了计算出次梁和板的可能的非线性响应，用梁单元为楼盖建立模型。
次梁按T型梁计算，翼缘的计算宽度为各自板厚的四倍【5】。
选取轴2和轴3的纵梁和其之间的一个宽20英寸的梁间的格栅为板的计算模型。
为了给出板沿横向的计算模型，同样用一个宽20英寸于横梁平行的梁。
在方形的板中其剪力流和梁单元的中的不一样。
所以其扭转刚度取为整个截面刚度的一半【9】。
图.5 梁的上部配筋弯曲位置（于梁A1-A2相似，在邻近建筑靠近柱A1的地方）图.6 典型的楼盖的次梁系统图.7 实验和分析的第二层柱A3的竖向位移建筑的2、4、5、6层有填充墙，并在门窗等开口位置有过梁，如前面提到的第1、三层的填充墙，在爆除前已经拆掉。
填充墙是用良好的空隙砖砌成的，空心砖的净空是其总大小的一半。
填充墙的平面效应增强了建筑的刚度和强度，并且影响建筑的对荷载反应即变形。
如果忽略墙的影响将得不到准确的建筑的刚度和强度。
在SAP2000中考虑了两种填充墙的形式：一种是用平面框架模型（模型A），另一种是FEMA365【10】中建议的受压杆件模型（模型B）。
4.1模型A是平面框架模型，但是，现行版本的SAP2000只能计算线性框架模型，不能计算裂缝的发展情况。
填充墙的抗拉强度大概为26psi，弹性模量为644ksi【10】。
由于裂缝的发展对填充墙的刚度影响很大，重复以下步骤来计算裂缝的形成：（1）假设填充墙是线性的而且没有开裂，运行非线性历史分析。
由于梁中的塑性铰的存在，梁中弯矩大于裂缝出现弯矩时候，对截面惯性矩有一个折减。
（2）判定填充墙出现的依据是看其应力于墙的抗拉强度大小关系。
（3）节点在拉应力大于抗拉强度的地方分离。
重复上面的步骤直到裂缝区域被确定。
4.2.模型B（受压杆件模型）如FEMA356【10】所述用受压杆件来代替填充墙，杆件的方向根据移除柱后的结构变形形式和开口位置确定。
4.3.柱的移除按以下步骤模拟柱的移除。
结构是在只受永久荷载下分析的，内力在柱端测定，将随着柱的移除而卸荷。
模型的建立是在移除第一层的柱A2、A3的情况下进行的。
结构同样是在永久荷载下进行静态分析的。
在此情况下，测得的柱端内力被当成永久外部荷载施加在结构上。
注意此分析结果跟第一步的分析是等价的。
第二步中大小相等方向相反的柱端力，被瞬间施加在原柱的位置上，然后进行动态分析。
4.4.实验和分析结果的比较结构计算最大竖向位移在第二层的柱A3上，图7所示为按模型A的实验和分析的梁A3竖向位移的比较。
实验数据是用三个粘在A3两端的传感器记录的。
实验和分析得到的最大位移分别是6.1mm和6.4mm，相差尽为4%。
实验和分析的位移产生所用时间分别为0.069S和0.066S。
分析结果显示永久位移为5.3mm，比实验结果小14%，实验结果为6.1mm。
图.8.第二层的柱A3在模型A和B下分别沿时间的竖向位移图.8.比较了第二层的柱A3分别在模型A和B下分析的沿时间的竖向位移。
由图中可以看出，按受压杆件模型（模型B）得出的最大竖向位移为11.4mm,比用模型A得出的结果高出约80%。
在图.7.可以看出按模型A得出的结果与实验结果是想接近的，B 模型得出的结构变形过高。
如果最大竖向位移偏大的话，填充墙开裂情况会更加严重，更偏向于受压杆件形成，模型A和模型B得出结果差异将减小。
图.9.比较了用模型A时第二层的柱A2的分析和实验的位移值。
同样，第一次达到最大位移值的实验和分析值非常接近，分析的永久位移值比实验的位移值略微低些。
图.10.所示为根据模型A得出的最大竖向位移的结构变形放大200倍后的情况。
图.9.第二层的柱A2竖向位移实验和分析结果比较图.10.按模型A，FEM分析的结构变形形式（第二层的实验得出变形形式也给出）通过实测得的变形形式在图中也用实线标出了。
在二层的梁A1-A2、A3-B3的上下端部应力重分配复杂的地方共用了14个电位计。
梁上部和对应的下部电位计接在一起用来测量梁的扭转变形。
用上下端部电位计的差值除以电位计的距离（沿梁高）。
分析推算的二层梁端部变形曲线如图中的曲线所示。
由图可以看出，分析的变形梁的变形曲线跟实验所得结果非常吻合。
根据模型A分析结果表明预示钢筋屈服的塑性铰只有两个，四个没有上部配筋的截面，到达屈服极限而开裂。
图.10.给出了所有的塑性铰及开裂位置。
Response of a reinforced concrete infilled-framestructure to removal of two adjacent columnsMehrdad Sasani_Northeastern University, 400 Snell Engineering Center, Boston, MA 02115,United StatesReceived 27 June 2007; received in revised form 26 December 2007;accepted 24 January 2008Available online 19 March 2008AbstractThe response of Hotel San Diego, a six-story reinforced concrete infilled-frame structure, is evaluated following the simultaneous removal of two adjacent exterior columns. Analytical models of the structure using the Finite Element Method as well as the Applied Element Method are used to calculate global and local deformations. The analytical results show good agreement with experimental data. The structure resisted progressive collapse with a measured maximum vertical displacement of only one quarter of an inch (6.4 mm). Deformation propagation over the height of the structure and the dynamic load redistribution following the column removal are experimentally and analytically evaluated and described. The difference between axial and flexural wave propagations is discussed. Three-dimensional Vierendeel (frame) action of the transverse and longitudinal frames with the participation of infill walls is identified as the major mechanism for redistribution of loads in the structure. The effects of two potential brittle modes of failure (fracture of beam sections without tensile reinforcement and reinforcing bar pull out) are described. The response of the structure due to additional gravity loads and in the absence of infill walls is analytically evaluated.c 2008 Elsevier Ltd. All rights reserved.Keywords: Progressive collapse; Load redistribution; Load resistance; Dynamic response; Nonlinear analysis; Brittle failure1. IntroductionAs part of mitigation programs to reduce the likelihood of mass casualtiesfollowing local damage in structures, the General Services Administration [1] and the Department of Defense [2] developed regulations to evaluate progressive collapse resistance of structures. ASCE/SEI 7 [3] defines progressive collapse as the spread of an initial local failure from element to element eventually resulting in collapse of an entire structure or a disproportionately large part of it. Following the approaches proposed by Ellingwood and Leyendecker [4], ASCE/SEI 7 [3] defines two general methods for structural design of buildings to mitigate damage due to progressive collapse: indirect and direct design methods. General building codes and standards [3,5] use indirect design by increasing overall integrity of structures. Indirect design is also used in DOD [2]. Although the indirect design method can reduce the risk of progressive collapse [6,7] estimation ofpost-failure performance of structures designed based on such a method is not readily possible. One approach based on direct design methods to evaluate progressive collapse of structures is to study the effects of instantaneous removal of load-bearing elements, such as columns. GSA [1] and DOD [2] regulations require removal of one load bearing element. These regulations are meant to evaluate general integrity of structures and their capacity of redistributing the loads following severe damage to only one element. While such an approach provides insight as to the extent to which the structures are susceptible to progressive collapse, in reality, the initial damage can affect more than just one column. In this study, using analytical results that are verified against experimental data, the progressive collapse resistance of the Hotel San Diego is evaluated, following the simultaneous explosion (sudden removal) of two adjacent columns, one of which was a corner column. In order to explode the columns, explosives were inserted into predrilled holes in the columns. The columns were then well wrapped with a few layers of protective materials. Therefore, neither air blast nor flying fragments affected the structure.2. Building characteristicsHotel San Diego was constructed in 1914 with a south annex added in 1924. The annex included two separate buildings. Fig. 1 shows a south view of the hotel. Note that in the picture, the first and third stories of the hotel are covered with black fabric. The six story hotel had a non-ductile reinforced concrete (RC) frame structure with hollow clay tile exterior infill walls. The infills in the annex consisted of two wythes (layers) of clay tiles with a total thickness of about 8 in (203 mm). The height of the first floor was about 190–800 (6.00 m). The height of other floors and that of the top floor were 100–600 (3.20 m) and 160–1000 (5.13 m), respectively. Fig. 2 shows the second floor of one of the annex buildings. Fig. 3 shows a typical plan of this building, whose response following the simultaneous removal (explosion) of columns A2 and A3 in the first (ground) floor is evaluated in this paper. The floor system consisted of one-way joists running in the longitudinal direction (North–South), as shown in Fig. 3. Based on compression tests of two concrete samples, the average concrete compressive strength was estimated at about 4500 psi (31 MPa) for a standard concrete cylinder. The modulus of elasticity of concretewas estimated at 3820 ksi (26 300 MPa) [5]. Also, based on tension tests of two steel samples having 1/2 in (12.7 mm) square sections, the yield and ultimate tensile strengths were found to be 62 ksi (427 MPa) and 87 ksi (600 MPa), respectively. The steel ultimate tensile strain was measured at 0.17. The modulus of elasticity of steel was set equal to 29 000 ksi (200 000 MPa). The building was scheduled to be demolished by implosion. As part of the demolition process, the infill walls were removed from the first and third floors. There was no live load in the building. All nonstructural elements including partitions, plumbing, and furniture were removed prior to implosion. Only beams, columns, joist floor and infill walls on the peripheral beams were present.3. SensorsConcrete and steel strain gages were used to measure changes in strains of beams and columns. Linear potentiometers were used to measure global and local deformations. The concrete strain gages were 3.5 in (90 mm) long having a maximum strain limit of ±0.02. The steel strain gages could measure up to a strain of ±0.20. The strain gages could operate up to a several hundred kHz sampling rate. The sampling rate used in the experiment was 1000 Hz. Potentiometers were used to capture rotation (integral of curvature over a length) of the beam end regions and global displacement in the building, as described later. The potentiometers had a resolution of about 0.0004 in (0.01 mm) and a maximum operational speed of about 40 in/s (1.0 m/s), while the maximum recorded speed in the experiment was about 14 in/s (0.35 m/s).4. Finite element modelUsing the finite element method (FEM), a model of the building was developed in the SAP2000 [8] computer program. The beams and columns are modeled with Bernoulli beam elements. Beams have T or L sections with effective flange width on each side of the web equal to four times the slab thickness [5]. Plastic hinges are assigned to all possible locations where steel bar yielding can occur, including the ends of elements as well as the reinforcing bar cut-off and bend locations. The characteristics of the plastic hinges are obtained using section analyses of the beams and columns and assuming a plastic hinge length equal to half of the section depth. The current version of SAP2000 [8] is not able to track formation of cracks in the elements. In order to find the proper flexural stiffness of sections, an iterative procedure is used as follows. First, the building is analyzed assuming all elements are uncracked. Then, moment demands in the elements are compared with their cracking bending moments, Mcr . The moment of inertia of beam and slab segments are reduced by a coefficient of 0.35 [5], where the demand exceeds the Mcr. The exterior beam cracking bending moments under negative and positive moments, are 516 k in (58.2 kN m) and 336 k in (37.9 kN m), respectively. Note that no cracks were formed in the columns. Then the building is reanalyzed and moment diagrams are re-evaluated. This procedure is repeated until all of the cracked regions are properly identified and modeled.The beams in the building did not have top reinforcing bars except at the end regions (see Fig. 4). For instance, no top reinforcement was provided beyond the bend in beam A1–A2, 12 inches away from the face of column A1 (see Figs. 4 and 5). To model the potential loss of flexural strength in those sections, localized crack hinges were assigned at the critical locations where no top rebar was present. Flexural strengths of the hinges were set equal to Mcr. Such sections were assumed to lose their flexural strength when the imposed bending moments reached Mcr.The floor system consisted of joists in the longitudinal direction (North–South). Fig. 6 shows the cross section of a typical floor. In order to account for potential nonlinear response of slabs and joists, floors are molded by beam elements. Joists are modeled with T-sections, having effective flange width on each side of the web equal to four times the slab thickness [5]. Given the large joist spacing between axes 2 and 3, two rectangular beam elements with 20-inch wide sections are used between the joist and the longitudinal beams of axes 2 and 3 to model the slab in the longitudinal direction. To model the behavior of the slab in the transverse direction, equally spaced parallel beams with 20-inch wide rectangular sections are used. There is a difference between the shear flow in the slab and that in the beam elements with rectangular sections modeling the slab. Because of this, the torsional stiffness is setequal to one-half of that of the gross sections [9].The building had infill walls on 2nd, 4th, 5th and 6th floors on the spandrel beams with some openings (i.e. windows and doors). As mentioned before and as part of the demolition procedure, the infill walls in the 1st and 3rd floors were removed before the test. The infill walls were made of hollow clay tiles, which were in good condition. The net area of the clay tiles was about 1/2 of the gross area. The in-plane action of the infill walls contributes to the building stiffness and strength and affects the building response. Ignoring the effects of the infill walls and excluding them in the model would result in underestimating thebuilding stiffness and strength.Using the SAP2000 computer program [8], two types of modeling for the infills are considered in this study: one uses two dimensional shell elements (Model A) and the other uses compressive struts (Model B) as suggested in FEMA356 [10] guidelines.4.1. Model A (infills modeled by shell elements)Infill walls are modeled with shell elements. However, the current version of the SAP2000 computer program includes only linear shell elements and cannot account for cracking. The tensile strength of the infill walls is set equal to 26 psi, with a modulus of elasticity of 644 ksi [10]. Because the formation ofcracks has a significant effect on the stiffness of the infill walls, the following iterative procedure is used to account for crack formation:(1) Assuming the infill walls are linear and uncracked, a nonlinear time history analysis is run. Note that plastic hinges exist in the beam elements and the segments of the beam elements where moment demand exceeds the cracking moment have a reduced moment of inertia.(2) The cracking pattern in the infill wall is determined by comparing stresses in the shells developed during the analysis with the tensile strength of infills.(3) Nodes are separated at the locations where tensile stress exceeds tensile strength. These steps are continued until the crack regions are properly modeled.4.2. Model B (infills modeled by struts)Infill walls are replaced with compressive struts as described in FEMA 356 [10] guidelines. Orientations of the struts are determined from the deformed shape of the structure after column removal and the location of openings.4.3. Column removalRemoval of the columns is simulated with the following procedure.(1) The structure is analyzed under the permanent loads and the internal forces are determined at the ends of the columns, which will be removed.(2) The model is modified by removing columns A2 and A3 on the first floor. Again the structure is statically analyzed under permanent loads. In this case, the internal forces at the ends of removed columns found in the first step are applied externally to the structure along with permanent loads. Note that the results of this analysis are identical to those of step 1.(3) The equal and opposite column end forces that were applied in the second step are dynamically imposed on the ends of the removed column within one millisecond [11] to simulate the removal of the columns, and dynamicanalysis is conducted.4.4. Comparison of analytical and experimental resultsThe maximum calculated vertical displacement of the building occurs at joint A3 in the second floor. Fig. 7 shows the experimental and analytical (Model A) vertical displacements of this joint (the AEM results will be discussed in the next section). Experimental data is obtained using the recordings of three potentiometers attached to joint A3 on one of their ends, and to the ground on the other ends. The peak displacements obtained experimentally and analytically (Model A) are 0.242 in (6.1 mm) and 0.252 in (6.4 mm), respectively, which differ only by about 4%. The experimental and analytical times corresponding to peak displacement are 0.069 s and 0.066 s, respectively. The analytical results show a permanent displacement of about 0.208 in (5.3 mm), which is about 14% smaller than the corresponding experimental value of 0.242 in (6.1 mm).Fig. 8 compares vertical displacement histories of joint A3 in the second floor estimated analytically based on Models A and B. As can be seen, modeling infills with struts (Model B) results in a maximum vertical displacement of joint A3 equal to about 0.45 in (11.4 mm), which is approximately 80% larger than the value obtained from Model A. Note that the results obtained from Model A are in close agreement with experimental results (see Fig. 7), while Model B significantly overestimates the deformation of the structure. If the maximum vertical displacement were larger, the infill walls were more severely cracked and the struts were more completely formed, the difference between the results of the two models (Models A and B) would be smaller.Fig. 9 compares the experimental and analytical (Model A) displacement of joint A2 in the second floor. Again, while the first peak vertical displacement obtained experimentally and analytically are in good agreement, the analytical permanent displacement under estimates the experimental value.Analytically estimated deformed shapes of the structure at the maximum vertical displacement based on Model A are shown in Fig. 10 with a magnification factor of 200. The experimentally measured deformed shape over the end regions of beams A1–A2 and A3–B3 in the second floorare represented in the figure by solid lines. A total of 14 potentiometers were located at the top and bottom of the end regions of the second floor beams A1–A2 and A3–B3, which were the most critical elements in load redistribution. The beam top and corresponding bottom potentiometer recordings were used to calculate rotation between the sections where the potentiometer ends were connected. This was done by first finding the difference between the recorded deformations at the top and bottom of the beam, and then dividing the value by the distance (along the height of the beam section) between the two potentiometers. The expected deformed shapes between the measured end regions of the second floor beams are shown bydashed lines. As can be seen in the figures, analytically estimated deformed shapes of the beams are in good agreement with experimentally obtained deformed shapes.Analytical results of Model A show that only two plastic hinges are formed indicating rebar yielding. Also, four sections that did not have negative (top) reinforcement, reached cracking moment capacities and therefore cracked. Fig. 10 shows the locations of all the formed plastic hinges and cracks.。