2023年全國碩士研究生考試考研英語一試題真題(含答案詳解+作文范文)_第1頁
已閱讀1頁,還剩4頁未讀, 繼續(xù)免費閱讀

下載本文檔

版權說明:本文檔由用戶提供并上傳,收益歸屬內容提供方,若內容存在侵權,請進行舉報或認領

文檔簡介

1、<p><b>  外文翻譯</b></p><p><b>  橋梁工程簡介</b></p><p>  橋梁是跨越如河流、山谷這樣障礙的一種建筑,從而提供交通便利,到目前為止,大部分橋梁都是公路橋或鐵路橋。大量的高架橋于19世紀在歐洲建成,目的是保持其運河中船舶的航行。最小的一座橋在紐約市的肯尼迪機場,它主要是把滑行飛機拖到跑道上服

2、務的。 人類建成的第一座橋類似于原始人在孤立地帶建成的。早期人類的工具和建筑技術如同原始人類一樣都是最初級的,他們只要經過最少的加工和安裝即可建成。 </p><p>  【關鍵字】 橋梁的發(fā)展 橋梁的種類</p><p><b>  1.橋梁的發(fā)展</b></p><p>  在森林里,隨處可得結實的木材和圓木,那時侯的橋極可能是由一根或并

3、排的幾根圓木建成,可能在其上覆一些木枝或草墊以方便行走。 </p><p>  處于熱帶地區(qū)的印度、非洲、和南美洲纖維藤被用來建成懸索橋,這些藤被系在小河或山谷兩邊的樹上或巖石上。一根或更多的藤被踩在上面行走,其它的則排列在膏腴幾英尺的地方,用作手扶用。雖然藤索橋通常不穩(wěn)定。但有很多用incas建成藤索橋有足夠的堅固和穩(wěn)定性,被用于西班牙士兵和它們馬匹的通行。 </p><p>  在巖石

4、地區(qū),石頭被用來建橋,橫跨河流以很小的間距布置石碓作為橋墩,然后用平坦的石頭橫過相鄰的橋墩就建成連接兩岸的通道,大部分的石橋就是這種類型,叫做鼓掌橋。現在在Dartmoor、英格蘭仍然可見,不過它們都建于中世紀甚至更晚。 </p><p>  原始橋梁的第一步變革被認為出現在中國古代,隨后傳入印度。河床一般比樹要寬,中國人和印度人在河流的中央建成兩個樹樁。在這個結構的兩端,用圓木的一端架在樹樁上并微微向上傾斜,使

5、其每一層都比它下面的高幾英尺。為了增加穩(wěn)定性,每個木樁在兩岸都用一堆大而重的石頭錨固;接近河中央,在河中間的兩個木樁的兩端則用簡支梁連接。在這種結構中,天然支架橋在兩個自由桿的中間加樁后可達到很寬的跨度。 </p><p>  早在公元前4000年的Mesopotamia和在公元千3000年的埃及,用石頭或日光烤干的磚被用來安裝重疊的橫梁。這種結構看起來像的拱,下部更平穩(wěn),被叫做突拱。要使突拱變?yōu)楦钡墓?,它需?/p>

6、石頭的內部構造適合光滑。這種直拱比突拱更堅固,且早在公元前500年就被使用。 </p><p>  這種直石拱具有經濟和經久耐用,它可以由許多靜止在碼頭上的拱而跨過小的河流。并且,它一般會經常出現,而它的質量比先前的任何結構都要好。在中國和羅馬的古代,這種整體石拱被廣泛地用于橋梁結構。它一直被廣泛地使用直到19世紀。 </p><p><b>  2.橋梁的種類</b>

7、;</p><p>  這里有4類基本結構可以用作水面上的或障礙物上的橋:剛架橋、懸臂橋、拱橋、和懸索橋體系。 </p><p>  剛架橋最簡單也可能是最早使用的-即剛架橋河流。這樣它的兩端固定在相對的河岸。這種剛架橋可以組成某種形狀的木梁、鋼筋混凝土梁或更復雜的約束。剛架橋這種類型的橋的跨度可以采用在中間建橋墩或在峽谷建擱柵撐,再用幾根橫梁連接起來而增加跨度。剛架橋的材料必須能夠承擔壓

8、力和拉力。盡管它的名字叫曲梁,但實際上這種具有雙重要求的桿能用于剛架橋上。結果,梁彎曲較高的部分的壓力比直的部分低一半以上,如果他的受壓承載力太弱,它將會成扣環(huán),如果受拉承載力太弱,他將會破壞。 </p><p>  懸臂橋在利用中間橋墩的長跨距橋中它通常是不可行的橋梁結構。舉個例子,在深而流速急的河流或軟泥中,可能很難建橋墩使它有足夠深度達到基巖層。在這種情況下,剛架橋結構用兩根橫梁就可以延伸―――從每岸伸出一

9、根梁,而在兩根梁的端部基礎進行錨固。這種簡單的剛架橋結構更具有靜定性,而每一根錨固的梁的這種基礎結構就叫懸臂橋,或許這種最簡單而熟悉的懸臂橋例子便是跳水板。在普通的懸臂式橋梁中,懸臂梁端部之間的間隙是閉合的,為道路提供了連續(xù)的橋面。但是假如把這種橋梁在其閉合點斷開,那么每一根懸臂梁都不需要另外設置支撐而可保持穩(wěn)定。通常懸臂梁中間間隙是閉合的既是剛架橋。如此卻使懸臂糧延伸了跨度。 </p><p>  懸索橋在沒有

10、中間橋墩的情況下比懸臂橋跨越更大的距離。懸索橋的支撐體系是靠連續(xù)可彎曲的纜繩的兩端的錨固,懸索橋最簡單的例子是雜技場高空走鋼絲雜技演員用的鋼絲。原始的懸索橋常常是一把很小的幾根這樣的鋼絲系在一起來提供扶手和立足點的。在水平公路上的現代懸索橋則是由纜繩懸吊在車行道兩邊的下面。 </p><p>  拱橋則是相反于懸索橋的作用,在那些懸索橋纜繩自由的提供支撐力的地方,拱橋卻是從它的兩端支柱固定的向上彎曲。由于在形狀上

11、的不同,懸索橋的纜繩的各點都趨向拉伸而拱橋的支柱的各處都趨于擠壓。由于這些原因,懸索橋的纜繩必須盡可能的防止延伸,餓拱橋材料則盡可能地抵抗壓縮。因為拱結構不一定要求材料具有抗拉強度,所以拱橋可以用磚或石頭建造,磚或石頭通過拱傳遞壓力的特性結合在一起。這種材料在其它的基本橋梁結構中卻毫無用處。 </p><p>  在拱橋中,荷載由公路上垂直傳遞下來,直到拱形遭到破壞。當拱遭到純壓而達到臨界荷載時,便會改變力的傳遞

12、路徑。有壓縮力的推力通過節(jié)點或墩傳到地面。拱這種簡單而優(yōu)美的結構成為橋梁中的一種基本結構。</p><p>  introduction to bridge engineering </p><p>  Bridges that span rivers, valleys such a barrier construction, which provides convenient trans

13、portation, so far, most of the bridges are highway bridges or railway bridge. A large number of viaducts built in the 19th century in Europe, aims to maintain its navigation of the ship canal. The smallest bridge in New

14、York City's Kennedy Airport, it is primarily the aircraft taxiing onto the runway to the service.</p><p>  Humans is similar to the first bridge built in the primitive built in isolated areas. Early huma

15、n tools and construction techniques as the original, like humans are the most junior. After they are at least as long as the processing and installation can be completed.</p><p>  【Key words】 development of

16、bridge, the type of bridge</p><p>  1. The development of bridge</p><p>  In the forest, widely available solid wood and logs, then most likely Hou bridge or by a few logs built side by side, ma

17、y, in its number of wooden sticks or straw mats on the cover for easy walking.</p><p>  In the tropical regions of India, Africa, and South America are used to build fiber rattan suspension bridge, the vines

18、 are tied to trees on both sides of the river or valley or rock. One or more above the walking cane to be stepped on, others are arranged in Gao Yu a few feet, for hand use. Although rattan rope bridge is usually unstabl

19、e. But there are many rattan rope bridge with incas built strong and stable enough, to be used for the Spanish soldiers and their horses to pass.</p><p>  In rocky areas, the stone is used to bridge across t

20、he river to a small stone pestle as piers spaced, and then use a flat stone across the pier adjacent to the channel linking the two sides completed, most of the stone bridge is this types, called the clap bridge. Now in

21、Dartmoor, England are still visible, but they are built in the Middle Ages or even later.</p><p>  The first step changes the original bridge was considered in ancient China, and then into India. Generally w

22、ider than the tree bed, Chinese and Indians in the center of the river into two stumps. In this structure, both ends of the frame with one end of logs on the stump, and tilted slightly upward so that each layer of high t

23、han a few feet below it. In order to increase stability, both sides each with a bunch of stakes in large and heavy stone anchor; close to the river, in the middle of the ri</p><p>  As early as 4000 BC in Me

24、sopotamia, and thousands in the year 3000 in Egypt, with stone or sun dried bricks were used to install the overlapping beams. This structure looks like the arch, the lower more stable, is called sudden arch. To suddenly

25、 arch into a more straight arch, it needs to fit the internal structure of the stone smooth. The arch straight arch stronger than sudden, and as early as 500 BC to be used.</p><p>  The stone arch with direc

26、t economic and durable, it can rest on the dock by a number of the arch and across the small river. And, it generally will always appear, and its quality in any structure to be better than the previous. In ancient China

27、and Rome, which is widely used in the overall stone arch bridge structure. It has been widely used until the 19th century.</p><p>  2. The type of bridge</p><p>  There are four categories of ba

28、sic structure can be used as water or obstructions on the bridge: rigid frame bridge, cantilever bridge, arch, and suspension system.</p><p>  The simplest bridge may be just the first use - or just the rive

29、r bridge. So that it is relatively fixed at both ends of the banks. This rigid frame bridge can form a shaped wooden beams, reinforced concrete beams or more complicated constraints. Just this type of bridge span of the

30、bridge pier was built in the middle can be used or built in the valley support joists, beams connected by a few and then increase the span. Rigid Frame material must be able to bear the stress and tension. Despite it<

31、/p><p>  Cantilever bridge piers in the use of long-span bridges the middle it is usually not feasible in the bridge structure. For example, in the deep and rapid river flow, or ooze, it may make it difficult t

32、o build sufficient depth of bridge pier foundation rock. In this case, just on the bridge structure can be extended with two beams --- out of a beam from each shore, and in the two ends of the beam anchorage basis. This

33、simple structure is more rigid frame bridge with static characterization, and e</p><p>  Suspension bridge in the absence than in the case of the middle pier cantilever bridge across the greater distance. Su

34、spension of the support system is a continuous flexible cables by the ends of the anchor, the suspension bridge is the simplest example of high-altitude high-wire acrobat with the circus wire. The original suspension bri

35、dge is often a very small few that is tied to steel rails and provide a foothold. At the level of the modern suspension bridge on the road is suspended by the cab</p><p>  Arch is the opposite effect on the

36、suspension bridge, suspension bridge cables in the freedom of those who provide support force where it is from the bridge pillars at both ends of its fixed upward. As different in shape, suspension bridge cables tend to

37、stretch all the points of the pillars of the bridge tends to squeeze everywhere. For these reasons, suspension of the cable must be as much as possible to prevent the extension of the bridge material is as hungry to resi

38、st compression. Because t</p><p>  In the arch, the load on the vertical transmission from the road down until the arch was destroyed. When the arch was pure pressure to achieve the critical load, they will

溫馨提示

  • 1. 本站所有資源如無特殊說明,都需要本地電腦安裝OFFICE2007和PDF閱讀器。圖紙軟件為CAD,CAXA,PROE,UG,SolidWorks等.壓縮文件請下載最新的WinRAR軟件解壓。
  • 2. 本站的文檔不包含任何第三方提供的附件圖紙等,如果需要附件,請聯(lián)系上傳者。文件的所有權益歸上傳用戶所有。
  • 3. 本站RAR壓縮包中若帶圖紙,網頁內容里面會有圖紙預覽,若沒有圖紙預覽就沒有圖紙。
  • 4. 未經權益所有人同意不得將文件中的內容挪作商業(yè)或盈利用途。
  • 5. 眾賞文庫僅提供信息存儲空間,僅對用戶上傳內容的表現方式做保護處理,對用戶上傳分享的文檔內容本身不做任何修改或編輯,并不能對任何下載內容負責。
  • 6. 下載文件中如有侵權或不適當內容,請與我們聯(lián)系,我們立即糾正。
  • 7. 本站不保證下載資源的準確性、安全性和完整性, 同時也不承擔用戶因使用這些下載資源對自己和他人造成任何形式的傷害或損失。

最新文檔

評論

0/150

提交評論