土木工程专业英语试题.docx

土木工程专业英语课程试题学生姓名： 刘文奇 学号： 2015610263 原文： Modern Buildings and Structural Materials Many great buildings built in earlier ages are still in existence and in use. Among them are the Pantheon and the Colosseum in Rome, Hagia Sophia in Istanbul; the Gothic churches of France and England, and the Renaissance cathedrals, with their great domes, like the Duomo in Florence and St. Peters in Rome.They are massive structures with thick stone walls that counteract the thrust of their great weight. Thrust is the pressure exerted by each part of a structure on its other parts.These great buildings were not the product of knowledge of mathematics and physics. They were constructed instead on the basis of experience and observation, often as the result of trial and error. One of the reasons they have survived is because of the great strength that was built into them-strength greater than necessary in most cases. But the engineers of earlier times also had their failure. In Rome, for example, most of the people lived in insulae, great tenement blocks that were often ten stories high. Many of them were poorly constructed and sometimes collapsed with considerable loss of life.Today, however, the engineer has the advantage not only of empirical information, but also of scientific data that permit him to make careful calculations in advance. When a modern engineer plans a structure, he takes into account the total weight of all its component materials. This is known as the dead load, which is the weight of the structure itself. He must also consider the live load, the weight of all the people, cars, furniture, machines, and so on that the structure will support when it is in use. In structures such as bridges that will handle fast automobile traffic, he must consider the impact, the force at which the live load will be exerted on the structure. He must also determine the safety factor, that is, an additional capability to make the structure stronger than the combination of the three other factors.The modern engineer must also understand the different stresses to which the materials in a structure are subject. These include the opposite forces of compression and tension. In compression the material is pressed or pushed together; in tension the material is pulled apart or stretched, like a rubber band. In addition to tension and compression, another force is at work, namely shear, which we defined as the tendency of a material to fracture along the lines of stress. The shear might occur in a vertical plane, but it also might run along the horizontal axis of the beam, the neutral plane, where there is neither tension nor compression.Altogether, three forces can act on a structure: vertical-those that act up or down; horizontal-those that act sideways; and those that act upon it with a rotating or turning motion. Forces that act at an angle are a combination of horizontal and vertical forces. Since the structures designed by civil engineers are intended to be stationary or stable, these forces must be kept in balance. The vertical forces, for example, must be equal to each other. If a beam supports a load above, the beam itself must have sufficient strength to counterbalance that weight. The horizontal forces must also equal each other so that there is not too much thrust either to the right or to the left. And forces that might pull the structure around must he countered with forces that pull in the opposite direction.One of the most spectacular engineering failures of modern times, the collapse of the Tacoma Narrows Bridge in 1940, was the result of not considering the last of these factors carefully enough. When strong gusts of wind, up to sixty-five kilometers an hour, struck the bridge during a storm, they set up waves along the roadway of the bridge and also a lateral motion that caused the roadway to fall. Fortunately, engineers learn from mistakes, so it is now common practice to test scale models of bridges in wind tunnels for aerodynamic resistance.The principal construction materials of earlier times were wood and masonry brick, stone, or tile, and similar materials. The courses or layers were bound together with mortar or bitumen, a tar-like substance or some other binding agent. The Greeks and Romans sometimes used iron rods or clamps to strengthen their buildings. The columns of the Parthenon in Athens, for example, have holes drilled in them for iron bars that have now rusted away. The Romans also used a natural cement called pozzolana, made from volcanic ash, that became as hard as stone under water.Both steel and cement, the two most important construction materials of modern times, were introduced in the nineteenth century. Steel, basically an alloy of iron and a small amount of carbon, had been made up to that time by a laborious process that restricted it to such special uses as sword blades. After the invention of the Bessemer process in 1856, steel was available in large quantities at low prices. The enormous advantage of steel is its tensile strength; that is, it does not lose its strength when it is under a calculated degree of tension, a force which, as we have seen, tends to pull apart many materials. New alloys have further increased the strength of steel and eliminated some of its problems, such as fatigue, which is a tendency for it to weaken as a result of continual changes in stress.Modern cement, called Portland cement, was invented in 1824. It is a mixture of limestone and clay, which is heated and then ground into a powder. It is mixed at or near the construction site with sand, aggregate (small stones, crushed rock, or gravel), and water to make concrete. Different proportions of the ingredients produce concrete with different strength and weight. Concrete is very versatile; it can be poured, pumped, or even sprayed into all kinds of shapes. And whereas steel has great tensile strength, concrete has great strength under compression. Thus, the two substances complement each other.They also complement each other in another way: they have almost the same rate of contraction and expansion. They therefore can work together in situations where both compression and tension are factors. Steel rods are embedded in concrete to make reinforced concrete in concrete beams or structures where tension will develop. Concrete and steel also form such a strong bond-the force that unites them-that the steel cannot slip within the concrete. Still another advantage is that steel does not rust in concrete. Acid corrodes steel, whereas concrete has an alkaline chemical reaction, the opposite of acid.Prestressed concrete is an improved form of reinforcement. Steel rods are bent into the shapes to give them the necessary degree of tensile strength. They are then used to prestress concrete, usually by pretensioning or posttensioning method. Prestressed concrete has made it possible to develop buildings with unusual shapes, like some of the modern sports arenas, with large spaces unbroken by any obstructing supports. The uses for this relatively new structural method are constantly being developed.The current tendency is to develop lighter materials. Aluminum, for example, weighs much less than steel but has many of the same properties. Aluminum beams have already been used for bridge construction and for the framework of a few buildings.Attempts are also being made to produce concrete with more strength and durability, and with a lighter weight. One system that helps cut concrete weight to some extent uses polymers, which are long chainlike compounds used in plastics, as part of the mixture.译文：现代建筑和结构材料 许多早期伟大建筑依然沿用至今。其中包括潘提翁神庙和罗马大斗兽场，伊斯坦布尔的圣索菲亚大教堂；法国和英国的哥特式教堂和文艺复兴时期的大教堂，有着巨大的圆顶，像佛罗伦萨和罗马的圣彼得大教堂。他们是巨大的结构，厚厚的石头墙，抵消了他们的巨大重量的推力。推力是一个结构的每一个部分在其其他部分所施加的压力。 这些伟大的建筑不是数学和物理知识的产物。它们不是在经验和观察的基础上，而是建立在试验和错误的结果上。它们幸存下来的其中一个原因是因为在大多数情况下，它们能承受的力大于它们需要的力。但早期的工程师也有他们的失败。例如在罗马，大多数人住在岛上，较大的公寓街区，往往有十层楼高。其中许多建造很差，时而会有倒塌和丧失生命的巨大损失。 然而，今天，工程师不仅有经验的信息，还有科学的数据，允许他事先仔细计算的优势。当一个现代的工程师构思一个结构时，他考虑到所有的组成材料的总重量。这就是被称为恒荷载，这是结构本身的重量。他还必须考虑活荷载，包括所有建筑在使用时的人，汽车，家具，机器的重量。在桥梁等结构中，将进行快速的汽车交通，他必须考虑力的活荷载将施加在结构上的影响。他还必须确定安全系数，也就是说，一个额外的能力，使结构比其他三个因素的组合更强大。 现代工程师还必须了解结构中材料所受的不同应力。这些措施包括相反的力压缩和张力。在压缩中材料被压或推在一起，在张力中材料被拉伸，就像一个橡皮筋。除了拉伸和压缩，另一种力在工作，即剪切，我们定义为材料沿应力线的断裂的趋势。剪切可能发生在一个垂直的平面上，但它也可能沿梁的水平轴作用，在中性面，既不受张力也不受压力。 总的来说，三种力可以作用于一个结构：垂直的为向上或向下；水平的为横向；还有一个扭转或旋转运动。作用在一个角度的力是水平和垂直力的组合。由于土木工程师设计的结构是固定的或稳定的，这些部位必须保持平衡。例如，垂直力必须是相等的。如果梁上作用荷载，梁本身必须有足够的强度来平衡重量。水平力也必须相互平等，这样就不会有太多的向左或向右的推力。可能拉周围的结构的作用力，必须有相反方向的作用力拉着它。 现代工程失败事例中最特别的一个，在1940年塔科马海峡大桥崩塌，是由于没有仔细考虑这些因素。当强阵风达每小时六十五公里，桥梁被风暴袭击，他们建立了沿桥的方向的波，是横向风，导致巷道下降。幸运的是，工程师们从错误中学习，所以现在常见的做法，是测试桥梁的模型在风洞中的空气阻力。 早期的主要建筑材料是木、砖、石、瓦，以及类似的材料。层与层用砂浆或沥青，焦油状物质或其他一些粘合剂结合在一起。希腊人和罗马人有时用铁杆或夹子来加固建筑物。例如在雅典的潘提翁神庙，有铁栅栏孔钻，现在已经生锈了。罗马人也用天然火山灰水泥，由火山灰制成，在水中变得像石头一样坚硬。 钢和水泥，现代最重要的两种建筑材料，是在第十九世纪生产出来的。钢，基本上是一种铁的合金和少量的碳，经过了一个艰苦的过程，并限制了它的特殊用途，如剑刃。1856在转炉炼钢法发明后，钢才以低价格大批量供货。钢的巨大优势是它的抗拉强度，也就是说，在可计算的张力下，它不失去它的强度，就像我们已经看到的，分离出了许多材料。新的合金进一步增加了钢的强度，并消除了一些问题，比如疲劳，它是应力连续变化削弱而导致的结果的一种趋势。 现代水泥，被称为波特兰水泥，是在1824发明的。它是石灰石和粘土的混合物，加热后再研磨成粉末。它在建筑附近的工地用沙子，骨料（小石块，碎石，或砾石），和水混合，制成混凝土。不同比例的成分产生不同强度和重量的混凝土。混凝土是非常通用的，它可以被浇筑，提升，甚至喷洒到各种形状。而钢筋有很大的抗拉强度，混凝土在抗压强度下具有很大的强度。因此，这两种物质相互补充。 他们也以另一种方式相互补充：他们几乎相同的收缩和膨胀速度。因此，他们在既有收缩又有拉伸的情况下可以一起工作。钢筋被嵌入混凝土中，使应力发展的混凝土梁或结构被加强。混凝土和钢也形成这样一个强大的粘结力，结合它们，使钢筋不能在混凝土内滑移。还有另一个优点是，钢在混凝土中不锈蚀。酸性会腐蚀钢筋，而混凝土的碱性化学反应，与酸性相反。 预应力混凝土是一种改进的混凝土形式。钢筋弯曲成给它们必要的拉伸强度的形状。然后它们被用于预应力混凝土，通常采用先张法或后张法。预应力混凝土使发展不寻常的形状的建筑物成为可能，像一些现代体育场馆，不被任何阻隔间断的大空间。这种相对较新的结构方法正在不断发展。 目前的趋势是开发更轻的材料。例如，铝的重量比钢轻，但具有许多相同的属性。铝梁已被用于桥梁建设和一些建筑物的框架。 在产生更多的强度和耐久性和较轻重量的混凝土上做了一些尝试。使用聚合物有助于在一定程度上减少混凝土的重量，它是塑料中用的长链化合物的混合物的组成部分。原文：Building Types and Design A building is closely bound up with people, for it provides people with the necessary space to work and live in.As classified by their use, buildings are mainly of two types: industrial buildings and civil buildings. Industrial buildings are used by various factories or industrial production while civil buildings are those that are used by people for dwelling, employment, education and other social activities.Industrial buildings are factory buildings that are available for processing and manufacturing of various kinds, in such fields as the mining industry, the metallurgical industry, machine building, the chemical industry and the textile industry. Factory buildings can be classified into two types: single-story ones and multi-story ones. The construction of industrial buildings is the same as that of civil buildings. However, industrial and civil buildings differ in the materials used and in the way they are used.Civil buildings are divided into two broad categories: residential buildings and public buildings. Residential buildings should suit family life. Each flat should consist of at least three necessary rooms: a living room, a kitchen and a toilet. Public buildings can be used in politics, cultural activities, administration work and other services, such as schools, office buildings, child-care centers, parks, hospitals, shops, stations, theatres, gymnasiums, hotels, exhibition halls, bath pools, and so on. All of them have different functions, which in turn require different design types as well.Housing is the living quarters for human beings. The basic function of housing is to provide shelter from the elements, but people today require much more than this of their housing. A family moving into a new neighborhood will want to know if the available housing meets its standards of safety, health, and comfort. A family will also ask how near the housing is to grain shops, food markets, schools, stores, the library, a movie theater, and the community center.In the mid-1960s a most important value in housing was sufficient space both inside and out. A majority of families preferred single-family homes on about half an acre of land, which would provide space for spare-time activities. In highly industrialized countries, many families preferred to live as far out as possible from the center of a metropolitan area, even if the wage earners had to travel some distance to their work. Quite a large number of families preferred country housing to suburban housing because their chief aim was to get far away from noise, crowding, and confusion. The accessibility of public transportation had ceased to be a decisive factor in housing because most workers drove their cars to work. People were chiefly interested in the arrangement and size of rooms and the number of bedrooms.Before any of the building can begin, plans have to be drawn to show what the building will be like, the exact place in which it is to go and how everything is to be done.An important point in building design is the layout of rooms, which should provide the greatest possible convenience in relation to the purposes for which they are intended. In a dwelling house, the layout may be considered under three categories: day, night, and services. Attention must be paid to the provision of easy communication between these areas. The day rooms generally include a dining-room, sitting-room and kitchen, but other rooms, such as a study, may be added, and there may be a hall. The living-room, which is generally the largest, often serves as a dining-room, too, or the kitchen may have a dining alcove. The night rooms consist of the bedrooms. The services comprise the kitchen, bathrooms, larder, and water-closets. The kitchen and larder connect the services with the day rooms.It is also essential to consider the question of outlook from the various rooms, and those most in use should preferably face south as much as possible. It is, however, often very difficult to meet the optimum requirements, both on account of the surroundings and the location of the roads. In resolving these complex problems, it is also necessary to follow the local town-planning regulations which are concerned with public amenities, density of population, height of buildings, proportion of green space to dwellings, building lines, the general appearance of new properties in relation to the neighbourhood, and so on.There is little standardization in industrial buildings although such buildings still need to comply with local town-planning regulations. The modern trend is towards light, airy factory buildings with the offices, reception rooms, telephone exchange, etc., house in one low building overlooking the access