建筑結構外文翻譯

1、<p><b>　　建筑結構</b></p><p>　　結構物是建筑物的一部分，它支承建筑物的重量。對于世界上至少半數(shù)以上的土木工程師來說，結構物大部分是土木工程結構。我們也必須明確： 任何建造的東西都是一個結構物（從飛機工程師的觀點來看，飛機也是一個結構物）。結構物可以一所住宅，可以是埃及的金字塔，安第斯山的耶穌雕像，或者是水瀨建造的橫貫加拿大河流的堰壩。一座房屋建筑物是一個有

2、屋頂?shù)慕Y構物，而土木工程結構設計的很大一部分就是房屋建筑結構的設計。建筑物作為一個整體來說，是由建筑師設計的，在人口稠密地區(qū)更是如此。對于給水工程師、污水處理工程師和市政工程師來說，結構物并不總是他們工作中的重要部分，但是一條道路或一條管道也是結構物，因為這兩者均支承荷載。</p><p>　　任何結構設計都包括基礎設計。最常見的基礎之一是混凝土柱或鋼支柱的基礎。這種基礎一般按柱的最大荷載設計通常為獨立（單柱）基

3、礎，當排成一列的單柱基礎太大,以致幾乎互相接觸時，最好把它連接起來形成連續(xù)（條形）基礎。連續(xù)基礎的土方開挖和混凝土澆灌費用比分別做成數(shù)個單柱基礎的同樣基礎要低廉。</p><p>　　聯(lián)合基礎就是其中的單獨基礎也會大得幾乎相互接觸的一種基礎，但它與條形基礎不同，它可以承受一排以上的柱子傳來的荷載。聯(lián)合基礎最終發(fā)展成筏式(底板或滿堂式)基礎，在這種基礎里，所有的單柱基礎聯(lián)合起來形成一整塊鋼筋混凝土板，其厚度可以變化

4、，但通常整塊的厚度相等 。 </p><p>　　結構設計本身包括兩個不同的任務：即決定主要構件尺寸和布置的結構設計；和用數(shù)學方法或圖解方法或者兩者并用對此結構進行分析，從而搞清楚在采用了所選特定構件的結構物中荷載是如何傳遞的。對于象房屋框架這樣的普通結構物已經研究出許多分析方法，因而其設計和分析相對說來比較容易，可能只需進行一、二次便可完成。</p><p>　　但是對于任何一個異乎尋

5、常的結構，分析和設計的工作必須要重復多次，直到經過多次計算以后才能找到一個堅固、穩(wěn)定而耐久的設計。造價低廉并不屬于設計的質量指標，但它卻很重要，因為一個造價很高的結構物可能不會建造起來，因此設計者所得的酬金也較少。</p><p>　　對于城市中的典型多層結構物，無論它是計劃用作辦公樓或者用作住宅，工程師設計的最主要的構件是樓板，理由有二：從建筑物底層向上每層都重復出現(xiàn)樓板；樓板對建筑物的靜荷載影響最大。事實上假

6、設樓板是唯一的靜荷載，那么靜荷載就能相當精確地計算出來。</p><p>　　通常樓板是采用鋼筋混凝土或者預應力混凝土，因為它們比鋼和木材的耐火性能好，這對高層建筑來說，是一個重要的考慮因素。樓板有兩種主要的型式：實心樓板和空心磚樓板（或肋形樓板）。在肋形樓板中，樓板的下半部分有一部分是空心的，這有很大的優(yōu)點，因為下半部的混凝土本來對樓板不會起加強作用，只會增加自重。因而，肋形樓板比實心樓板輕得多，但要澆注具有貫

7、穿式孔洞的肋形樓板是比較困難的，除非事先把這些孔洞十分仔細得布置好。要澆注穿過實心樓板的孔洞時，在孔洞四周的混凝土中加設少量直徑12毫米的附加鋼筋，一般就可期安全。但如果時間充裕，對孔洞必須進行適當?shù)脑O計。</p><p>　　對于大多數(shù)多層建筑來說，由于城市地價很高，所以在結構本身還處于非常初步的設計階段時，基礎就必須很快的設計出來。但是，建筑物的設計必須已經進行到至少能知道柱子的位置，從而可以確定樓板的跨度的

8、階段，這樣就能夠算出樓板的大致厚度。即使各層樓板厚度真的有所不同，也只是稍作修改，而且必須盡可能精確的把面層計算在內。一般說來，13厘米厚的密實混凝土就已足夠，加上5厘米的墊層和樓板面層，總厚為18厘米。梁、柱和樓梯的重量可認為已包括在樓板的厚度內，如果樓板計劃用空心磚或輕骨料建造，則板的應當減薄 。</p><p>　　結構重量的最初粗略計算方法如下:假設各層樓板的總面積均相同,包括一層地下室在內(地下室的地面

9、不是懸空的,而是放在地基上)共有八層樓板,則包括屋頂在內的建筑物總靜荷載,以建筑物基礎每平方米計,其值為:9*18/100*2.75=4.45噸/米2。</p><p>　　一立方米密實混凝土還應加上活荷載值。如果這幢建筑物是住宅,則一層樓板的結構設計采用190公斤/米2的活荷載一般已經足夠。比值在大多數(shù)地方當局的建筑附加法規(guī)中得到承認。但是由于所有樓板可以滿載是不可能出現(xiàn)的,所以一般說來各地方當局從不堅持主張把

10、此荷載都作用在基礎上。在任何情況下,目前所計算的基礎厚度不受附加法規(guī)的控制,因而我們可以合理地采用活荷載的任意一部分。</p><p>　　懸掛結構是當前最令人感興趣的結構之一，因為最初的幾個大型懸掛結構已在1966年于倫敦或者可能還在其他大城市中建成。在所有這些結構中，柱子或支柱的數(shù)量較少而尺寸較大，以便降低對它們的壓曲作用，增加其有效長度。在倫敦建成的兩幢建筑物，在建筑物的中心只有一個支柱，這個支柱是一個面積

11、約12米見方的空心混凝土塔架，它支承著設在其內部的或懸設在其壁上的電梯、樓梯、風道、管道和電纜。塔架可以稱為建筑物的核心結構，在其頂部有一個向各個方向懸挑的橋，從橋上伸下高強鋼筋懸吊其下面的樓板。這些鋼筋很細，能夠隱藏在門框或窗框里，因此就這種建筑物而言，對視線不一定有什么明顯的障礙，或妨礙人們從核心部分往外向任何方向水平往來的活動。</p><p>　　然而，這僅僅是懸掛結構的開始，假如它能取得成功，而且假如世

12、界上的大城市中人口仍然越來越稠密，這種設計思想將會得到發(fā)展。而紐約的那些60層摩天大樓比起世界未來城市的碩大無比的300層結構來，將是多么渺小。</p><p>　　看來可能而且很有可能的情景是整個城市可能就是一座或者數(shù)座這樣巨大的建筑物，這些建筑物支承在成對的1000米高的塔架上，用輕型橋梁結構連通，可能采用的是懸索橋。為了減少擺動和壓曲現(xiàn)象，柱子將做的很大，可能不少于30米見方，而樓板所用細的高強鋼吊桿懸掛于

13、橋上，宛如懸索吊橋的橋面結構懸掛于吊索上一樣。</p><p>　　Building Structure</p><p>　　A structure is the part of a building that carries its weight, and for at least half the world’s civil engineers, structures are most

14、 of civil engineering. We should also remember that anything built is a structure. (From an aero-plane engineer’s point of view, an aero-plane also is a structure.) A structural design is the design of building structure

15、s. The building as a whole is designed by an architect, particularly in a densely populated area. For water engineers, sewage-treatment engineers,</p><p>　　Every structural design includes the foundation de

16、sign. One of the commonest foundations is that for a concrete column or a steel stanchion. It is generally designed for the same maximum load as the column, and usually is an independent (pad) foundation. Where the pads

17、in one row become so large that they nearly touch, it is convenient to join them into a continuous ( or trip) for foundation which generally will be cheaper to dig and to concrete than the same foundations built separate

18、ly as pads</p><p>　　Combined footings are those in which the pads would also be so large that they nearly touch, but unlike strip footings, they may carry the load from more than one row of columns. The fina

19、l development of the combined footing is the raft (or mat or matters) foundation in which all the pads are combined into one reinforced concrete slab which may vary in thickness, but is usually of the same thickness thro

20、ughout its area.</p><p>　　The structural design itself includes two different tasks, the design of the structure, in which the sizes and locations of the main members are settled, and the analysis of this st

21、ructure by mathematical or graphical methods or both, to work out how the loads pass through the structure with the particular members chosen. For a common structure such as a building frame, many methods have been devel

22、oped for analysis, so that the design and analysis will be relatively easy and may need to be perfo</p><p>　　But for any unusual structure the tasks of design and analysis will have to be repeated many times

23、 until, after many calculations, a design has been found that is strong, stable and lasting. Cheapness does not enter into the quality of the design though it is important since a costly structure will probably not be bu

24、ilt and the designer’s fee will therefore be smaller.</p><p>　　For the typical multi-story structure in a city, whether it is to be used for offices or dwellings, the most important member which the engineer

25、 designs is the floor—for two reasons: it repeats all the way up the building, and it has the greatest effect on the dead load of the building. The dead load, in fact, as pointed out in ‘foundations’, can be fairly exact

26、ly calculated by assuming that the floors are the only dead load.</p><p>　　These floors are generally of reinforced or prestressed concrete because they resist fire better than steel or wood, an important co

27、nsideration for a tall building. There are two main types, the solid floor and the hollow-tiled (or ribbed ) floor. In fact, in the ribbed floor, part of the lower half of the slab is hollow, a great advantage because th

28、is concrete would not strengthen the floor but would be heavy. Ribbed floors are therefore lighter than solid floors, but it is more difficult to ca</p><p>　　For most multi-storey buildings, because of the h

29、igh cost of the land in a city , the structure itself is in a very early stage of design at a time when the foundations must be designed very quickly. The building design must, however, have processed so far that at leas

30、t the positions of the columns are known, and therefore the floor spans will be fixed. The probable floor thickness can then be worked out. This will vary only slightly if at all from floor to floor, and it must be calcu

31、lated as cl</p><p>　　The first rough calculation of the structure weight is as follows: assuming the floors are all of the same total area, and there are eight floors including one basement not suspended but

32、 resting on the soil, the total dead weight of the building including the roof will be, per m2 of building foundation, 9*18/100*2.75=4.45 tons/m2 , the weight of 1 m3 of dense concrete being assumed to be 2.75 tons/m3.To

33、 this must be added a figure for the live load. If the building is to be for housing, a live l</p><p>　　Suspended structures are among the most interesting at the moment because the first large ones were in

34、1966 completed in London, and possibly other great cities. In all these structures, these columns or stanchions are made fewer and larger so as to reduce the bucking effects on them and to increase their effective length

35、. In two that were built in London, there is only one column, in the center of the building, and this is a hollow concrete tower some 12 m square which carries the lifts, stairs</p><p>　　But this is only the

36、 beginning of suspended construction. If it is successful and if the world’s large cities continue to become more crowded , the idea will grow, and the 60-storey skyscrapers of New York will be tiny compared with the vas

37、t 300-storey structures of the world’s future cities.</p><p>　　It seems possible and even likely that the whole city may be one or a few of these vast buildings, carried on pairs of towers 1,000 m high joine

38、d by lightweight bridge structures, possibly suspension bridge. To reduce sway and buckling, the columns will be massive, probably not less than 30 m square, and the floors will hang from the bridges by thin high-tension