土木工程專業(yè)英語試題

1、 土木工程專業(yè)英語課程試題學(xué)生姓名： 劉文奇 學(xué)號： 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 Renais

2、sance 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 no

3、t 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

4、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 en

5、gineer 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 t

6、he 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

7、 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

8、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 shea

9、r, 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 str

10、ucture: 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 stationar

11、y 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 mu

12、ch 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 c

13、onsidering 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 mist

14、akes, 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

15、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 calle

16、d 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

17、 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 unde

18、r 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 c

19、ement, 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 t

20、he 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 ot

21、her.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 structu

22、res 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 opp

23、osite 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 t

24、o 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, weigh

25、s 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

26、concrete weight to some extent uses polymers, which are long chainlike compounds used in plastics, as part of the mixture.譯文：現(xiàn)代建筑和結(jié)構(gòu)材料 許多早期偉大建筑依然沿用至今。其中包括潘提翁神廟和羅馬大斗獸場，伊斯坦布爾的圣索菲亞大教堂；法國和英國的哥特式教堂和文藝復(fù)興時(shí)期的大教堂，有著巨大的圓頂，像佛羅倫薩和羅馬的圣彼得大教堂。他們是巨大的結(jié)構(gòu)，厚厚的石頭墻，抵消了他們的巨大重量的推力。推力是一個(gè)結(jié)構(gòu)的每一個(gè)部分在其其他部分所施加的壓力。 這些偉大的建筑不是數(shù)學(xué)和物理知

27、識的產(chǎn)物。它們不是在經(jīng)驗(yàn)和觀察的基礎(chǔ)上，而是建立在試驗(yàn)和錯誤的結(jié)果上。它們幸存下來的其中一個(gè)原因是因?yàn)樵诖蠖鄶?shù)情況下，它們能承受的力大于它們需要的力。但早期的工程師也有他們的失敗。例如在羅馬，大多數(shù)人住在島上，較大的公寓街區(qū)，往往有十層樓高。其中許多建造很差，時(shí)而會有倒塌和喪失生命的巨大損失。 然而，今天，工程師不僅有經(jīng)驗(yàn)的信息，還有科學(xué)的數(shù)據(jù)，允許他事先仔細(xì)計(jì)算的優(yōu)勢。當(dāng)一個(gè)現(xiàn)代的工程師構(gòu)思一個(gè)結(jié)構(gòu)時(shí)，他考慮到所有的組成材料的總重量。這就是被稱為恒荷載，這是結(jié)構(gòu)本身的重量。他還必須考慮活荷載，包括所有建筑在使用時(shí)的人，汽車，家具，機(jī)器的重量。在橋梁等結(jié)構(gòu)中，將進(jìn)行快速的汽車交通，他必須考慮力

28、的活荷載將施加在結(jié)構(gòu)上的影響。他還必須確定安全系數(shù)，也就是說，一個(gè)額外的能力，使結(jié)構(gòu)比其他三個(gè)因素的組合更強(qiáng)大。 現(xiàn)代工程師還必須了解結(jié)構(gòu)中材料所受的不同應(yīng)力。這些措施包括相反的力壓縮和張力。在壓縮中材料被壓或推在一起，在張力中材料被拉伸，就像一個(gè)橡皮筋。除了拉伸和壓縮，另一種力在工作，即剪切，我們定義為材料沿應(yīng)力線的斷裂的趨勢。剪切可能發(fā)生在一個(gè)垂直的平面上，但它也可能沿梁的水平軸作用，在中性面，既不受張力也不受壓力。 總的來說，三種力可以作用于一個(gè)結(jié)構(gòu)：垂直的為向上或向下；水平的為橫向；還有一個(gè)扭轉(zhuǎn)或旋轉(zhuǎn)運(yùn)動。作用在一個(gè)角度的力是水平和垂直力的組合。由于土木工程師設(shè)計(jì)的結(jié)構(gòu)是固定的或穩(wěn)定的

29、，這些部位必須保持平衡。例如，垂直力必須是相等的。如果梁上作用荷載，梁本身必須有足夠的強(qiáng)度來平衡重量。水平力也必須相互平等，這樣就不會有太多的向左或向右的推力。可能拉周圍的結(jié)構(gòu)的作用力，必須有相反方向的作用力拉著它。 現(xiàn)代工程失敗事例中最特別的一個(gè)，在1940年塔科馬海峽大橋崩塌，是由于沒有仔細(xì)考慮這些因素。當(dāng)強(qiáng)陣風(fēng)達(dá)每小時(shí)六十五公里，橋梁被風(fēng)暴襲擊，他們建立了沿橋的方向的波，是橫向風(fēng)，導(dǎo)致巷道下降。幸運(yùn)的是，工程師們從錯誤中學(xué)習(xí)，所以現(xiàn)在常見的做法，是測試橋梁的模型在風(fēng)洞中的空氣阻力。 早期的主要建筑材料是木、磚、石、瓦，以及類似的材料。層與層用砂漿或?yàn)r青，焦油狀物質(zhì)或其他一些粘合劑結(jié)合在一

30、起。希臘人和羅馬人有時(shí)用鐵桿或夾子來加固建筑物。例如在雅典的潘提翁神廟，有鐵柵欄孔鉆，現(xiàn)在已經(jīng)生銹了。羅馬人也用天然火山灰水泥，由火山灰制成，在水中變得像石頭一樣堅(jiān)硬。 鋼和水泥，現(xiàn)代最重要的兩種建筑材料，是在第十九世紀(jì)生產(chǎn)出來的。鋼，基本上是一種鐵的合金和少量的碳，經(jīng)過了一個(gè)艱苦的過程，并限制了它的特殊用途，如劍刃。1856在轉(zhuǎn)爐煉鋼法發(fā)明后，鋼才以低價(jià)格大批量供貨。鋼的巨大優(yōu)勢是它的抗拉強(qiáng)度，也就是說，在可計(jì)算的張力下，它不失去它的強(qiáng)度，就像我們已經(jīng)看到的，分離出了許多材料。新的合金進(jìn)一步增加了鋼的強(qiáng)度，并消除了一些問題，比如疲勞，它是應(yīng)力連續(xù)變化削弱而導(dǎo)致的結(jié)果的一種趨勢。 現(xiàn)代水泥，被

31、稱為波特蘭水泥，是在1824發(fā)明的。它是石灰石和粘土的混合物，加熱后再研磨成粉末。它在建筑附近的工地用沙子，骨料（小石塊，碎石，或礫石），和水混合，制成混凝土。不同比例的成分產(chǎn)生不同強(qiáng)度和重量的混凝土?；炷潦欠浅Ｍㄓ玫模梢员粷仓?，提升，甚至噴灑到各種形狀。而鋼筋有很大的抗拉強(qiáng)度，混凝土在抗壓強(qiáng)度下具有很大的強(qiáng)度。因此，這兩種物質(zhì)相互補(bǔ)充。 他們也以另一種方式相互補(bǔ)充：他們幾乎相同的收縮和膨脹速度。因此，他們在既有收縮又有拉伸的情況下可以一起工作。鋼筋被嵌入混凝土中，使應(yīng)力發(fā)展的混凝土梁或結(jié)構(gòu)被加強(qiáng)。混凝土和鋼也形成這樣一個(gè)強(qiáng)大的粘結(jié)力，結(jié)合它們，使鋼筋不能在混凝土內(nèi)滑移。還有另一個(gè)優(yōu)點(diǎn)是

32、，鋼在混凝土中不銹蝕。酸性會腐蝕鋼筋，而混凝土的堿性化學(xué)反應(yīng)，與酸性相反。 預(yù)應(yīng)力混凝土是一種改進(jìn)的混凝土形式。鋼筋彎曲成給它們必要的拉伸強(qiáng)度的形狀。然后它們被用于預(yù)應(yīng)力混凝土，通常采用先張法或后張法。預(yù)應(yīng)力混凝土使發(fā)展不尋常的形狀的建筑物成為可能，像一些現(xiàn)代體育場館，不被任何阻隔間斷的大空間。這種相對較新的結(jié)構(gòu)方法正在不斷發(fā)展。 目前的趨勢是開發(fā)更輕的材料。例如，鋁的重量比鋼輕，但具有許多相同的屬性。鋁梁已被用于橋梁建設(shè)和一些建筑物的框架。 在產(chǎn)生更多的強(qiáng)度和耐久性和較輕重量的混凝土上做了一些嘗試。使用聚合物有助于在一定程度上減少混凝土的重量，它是塑料中用的長鏈化合物的混合物的組成部分。原文

33、：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 in

34、dustrial 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 meta

35、llurgical 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 d

36、iffer 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

37、. 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 functio

38、ns, 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

39、 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

40、 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 wag

41、e 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 housin

42、g 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

43、 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 m

44、ust 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, to

45、o, 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

46、, 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-plann

47、ing 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