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1、<p><b>  外文翻譯</b></p><p>  Quick fix: replacement of an old wooden bridge in </p><p>  St Petersburg was completed earlier this year.</p><p>  Rising traffic levels

2、 and development demands led to an old tramway bridge being rebuilt as a cable-stayed crossing in the Russian city of St Petersburg. The new Lazarevsky Bridge across the Malaya Nevka was opened to traffic earlier this ye

3、ar, replacing an old wooden structure which was built for trams but recently had only been used by pedestrians. </p><p>  The bridge is located in Petrograd district and connects Krestovsky and Petrogradsky

4、Islands along Pionerskaya and Sportivnaya Streets, both of which are importanat links for local traffic. When it was built in 1949, the crossing was called the Koltovsky Bridge, after the adjacent Malaya Nevka river emba

5、nkment. But in 1952, it was renamed to commemorate the legendary Russian admiral Mikhail Lazarev. The embankment and the bridge were redesignated the Admiral Lazarev Embankment and Lazarevsky Bri</p><p>  Bu

6、ilt to the design of engineer VV Blazhevich, the original bridge had 11 spans, the central one being a single-leaf drawspan. It was originally designed for trams and was the only tramway bridge in the city at that time.

7、Its total length was 141m and its width was 11m, the deck consisting of metal baulks and wooden plank flooring. The timber post piers rested on piled foundations of steel pipes. But in 2002 the tramway was closed and sin

8、ce then, the bridge has only been used by pedestrians. </p><p>  Its location meant that Lazarevsky Bridge served the western part of the city--the Petrograd districts including Krestovsky island. All the ro

9、ad traffic to Krestovsky island used the main Krestovsky Bridge which as a consequence was considerably overloaded. Since the Lazarevsky Bridge carried no vehicular traffic it was not considered part of the road network

10、of the district. But plans to build a new stadium at the Seaside Victory Park on Krestovsky Island just 3km from the bridge site meant tha</p><p>  The size of new bridge was determined based on the predicte

11、d traffic levels, taking into account the prospective development of the district. According to the forecast, the annual average daily traffic intensity on Lazarevsky Bridge will rise to 16,000 vehicles per day by 2025.

12、Peak loads occur during major sporting events at the stadium when the bridge will be required to help relieve the area of traffic within one hour. This traffic flow includes 4,500 to 5,000 cars, so even if the Petrovsky

13、B</p><p>  Taking into consideration the fact that the timber structures of the bridge had been in use for more than 55 years, if the bridge reconstruction had been restricted to the widening and strengtheni

14、ng of the existing superstructure and piers, it would not have ensured the longevity of the fixed bridge and might have led to high operation costs. Another consideration was that the appearance of a multi-span structure

15、 with bulky piers would not have fitted into the architectural style that is emergin</p><p>  As a result, the decision was taken to completely demolish the existing bridge and replace it with a new structur

16、e on the same alignment. As part of the project, some of Sportivnaya Street on the right bank had to be widened, and improvement of the adjacent area was also included. </p><p>  The history of the project d

17、ates back more than a decade to 1998, when JSC Institute Strojproect won the tender to carry out a feasibility study into the reconstruction of Lazarevsky Bridge and its approaches. </p><p>  Even at this ti

18、me, the architect Igor Serebrennikov had developed an original architectural concept of the bridge which involved use of a cable-stayed system. This concept was approved by the city's committee for development but fi

19、nancial problems meant that the design was suspended for seven years before it resumed. </p><p>  In 2003, the project was included in the target programme of design and survey works, and the tender for desi

20、gn development was officially announced. Again these works were awarded to JSC Institute Strojproect. The reconstruction design was completed in 2007 and was received positively by the State Expert Review Board; construc

21、tion began at the end of that year. </p><p>  The structural concept of the bridge was approved based on the comparison of technical and economical options. One of the main restrictions was the strict limita

22、tion on the superstructure construction depth. On the one hand, it was limited by the need to maintain underbridge clearance for navigation, while on the other hand the deck level was governed by the height of Admiral La

23、zarev Embankment, which could not be raised, according to the requirements of the committee for protection of monuments</p><p>  To meet these almost incompatible conditions it was necessary to make the long

24、itudinal profile of the deck with a vertical curve of radius 1,000m, a radius which is allowable only for very constrained conditions. But even with this minimum vertical curve radius, the limitation for the deck constru

25、ction depth remained fairly strict--it had to be 1.4m at the maximum. This condition could be met either by a classic five-span continuous beam scheme or by a cable-stayed system. The costs of both opti</p><p&

26、gt;  The unconventional appearance of the structure, particularly the shape of the tower and its asymmetric arrangement with its single span, put demands on the design abilities of the engineers from JSC Institute Strojp

27、roect, requiring them to cope with non-standard problems. One such problem was the need to provide the required rigidity to the deck while at the same time minimising its weight in order to decrease the moments in the to

28、wer elements and balance the system. Hence a single-span cable-st</p><p>  The deck consists of a system of longitudinal and transverse H-beams connected via the orthotropic slab with its U-shape stiffeners.

29、 The anchorages are located along the transverse beams. At the tower, the deck is rigidly fixed and at pier one it rests on Maurer spherical bearings. The steel part of the deck is made of low-alloy steel grade 10 and 15

30、 and the tower of steel grade 10 (400MPa). </p><p>  The cable stays are VSL standard monostrands and each one is made up of from 50 to 73 strands. The total length of strand used in the bridge is about 31km

31、. Meanwhile the bridge deck pavement consists of two layers of asphalt/concrete 40mm and 50mm placed over the Technoelastomost-S membrane waterproofing layer. </p><p>  The pier foundations are formed of hig

32、h pile caps resting on bored piles driven deep into the bearing stratum of firm clay. Above the foundation top, the piers are made of cast in situ concrete and faced with granite. </p><p>  Construction was

33、carried out by Mostootryad No 75, a branch of OAO Mostotrest No 6, while the steel deck structure was manufactured by JSC Zavod Metallokonstruktsiy and the steel tower structure was manufactured by NPO Mostovik. </p&g

34、t;<p>  For development of the detail design the specialists of automation division of the Institute prepared complex 3-D models of the tower and cable stay anchorages in PRO-E software which were used for analysi

35、s and as a basis for the fabrication of the structures by NPO Mostovik. The use of this successful PRO-E modelling enabled the complicated tower structures to be manufactured within a relatively short time. </p>&

36、lt;p>  Taking into consideration the constraints imposed on the bridge construction, JSC Institute Strojproect suggested some modifications to the detailed design. One such proposal was to replace the cable backstays

37、of the tower with rigid ties made of low-alloy steel grade 10 which would be fixed rigidly at the tower arches and counterweight. Temporary supports would be installed under the deck anchorages </p><p>  The

38、se modifications allowed the erection of the back-stays to be considerably simplified, and would also eliminate the need to tension the backstays, cutting in half the time for the cable-stay installation. </p><

39、;p>  In addition it meant that the cable-stays supporting the deck could be tensioned in a single operation, once the asphalt and concrete pavement had been installed on the bridge. Analysis included successive tensio

40、ning of cable-stay pairs from the longest pair down to the shortest pair with the subsequent final tensioning of the two longest pairs. Apart from the forces, the vertical displacements of the deck at the 'breakaway&

41、#39; points on the temporary supports had to be controlled. The actual tensi</p><p>  In fact it took the general contractor only 17 months to complete construction of all the works involved in the bridge co

42、nstruction. The new cable-stayed bridge has fitted harmoniously into the surrounding landscape. By avoiding placement of intermediate piers in the riverbed it was possible to open up views along the Malaya Nevka. The arc

43、h tower acts as a symbolic gateway to the island and stands out distinctly against its background of sky and trees. The architectural expressiveness of the bri</p><p>  Tatiana Gurevich is project manager an

44、d Yuri Krylov is head of the structural steel department at JSC Institute Strojproect</p><p><b>  橋梁的快速修復</b></p><p>  ——圣彼得堡一座舊木橋今年的更換工作</p><p>  在俄羅斯的圣彼得堡,崛起的交通水平和發(fā)展要求

45、促使一個舊的電車軌道橋被改造為一個斜拉橋。新的Lazarevsky大橋橫跨馬來亞內(nèi)芙卡,并與今年早些時候建成通車,取代了一座本來供有軌電車通行但是現(xiàn)在只供行人行走的舊木質橋。</p><p>  這座橋坐落于彼得格勒區(qū),并且沿著Pionerskaya和Sportivnaya街道將Krestovsky和Petrogradsky群島連接了起來,這兩者都是當?shù)氐慕煌屑~。它始建于1949年,當時被稱為Koltovsky

46、橋,相鄰馬來亞內(nèi)芙卡河堤。但在1952年,為了紀念傳說中的俄羅斯海軍上將米哈伊爾拉扎列夫,路堤及橋梁被易名為拉扎列夫海軍上將路堤和Lazarevsky橋。</p><p>  這座橋由VV Blazhevich工程師設計,最初橋有11跨,中央一個是單葉。它最初是設計用于電車,并且是當時該市唯一的一座電車軌道橋??傞L度為141m,總寬度為11m,層面由金屬和木質材料組成。木材支柱支撐的碼頭建在鋼管樁基礎上。但是在2

47、002年時,電車軌道被關閉,從那時起,這座橋只供行人使用。</p><p>  這座橋梁的位置就意味著它服務這座城市的西部——包括Krestovsky島的彼得格勒區(qū)。所有到Krestovsky島的車輛都用主要這個島的Krestovsky橋,這自然導致該橋大大超載。由于Lazarevsky橋并沒有承受車輛荷載,所以它不被認為是彼得格勒區(qū)的交通網(wǎng)絡的一部分。但是,Krestovsky島上計劃在victory公園里興建

48、一個體育場,離海邊僅有3公里,這意味著城市的其余部分需要一個可靠的連接方式。當?shù)卣J為解決這個問題最好的辦法就是重建Lazarevsky橋。</p><p>  新橋的規(guī)模取決于現(xiàn)有交通水平,并且考慮到了該地區(qū)未來的發(fā)展。據(jù)預測,到2025年,Lazarevsky橋的全年平均日交通量將上升至16000車次。車流高峰發(fā)生在體育場館舉行重大賽事時,此時該橋須能在一小時內(nèi)紓緩這個地段的交通。這股交通流包括4,500至

49、5,000輛車,所以即使Petrovsky橋能夠重建,Lazarevsky橋也需要雙向四車道來達到疏通效果。</p><p>  考慮到這座木質橋已經(jīng)使用了55年以上,如果在限制上層建筑寬度和加強現(xiàn)有上層建筑的基礎上重建,也許不能保證橋梁的壽命,而且會導致產(chǎn)生較高的運營成本。另外一個值得考慮的問題是,一個擁有龐大突堤的多跨橋的外觀不會與現(xiàn)代建筑和鄰近堤岸的風格相融合。</p><p>  

50、因此,人們決定徹底拆除現(xiàn)存的橋梁,再在原來的位置上建造一座新的橋梁。作為項目的一部分,右岸Sportivnaya街道的一部分必須加寬,并且還要改善鄰近的地區(qū)。</p><p>  這個項目的歷史可以追溯到1998年,那是JSC研究所剛剛中標,它提出了一套對Lazarevsky橋進行重建的方法。</p><p>  即使在這個時候,建筑師伊戈爾謝列布連尼科夫曾經(jīng)提出過一種關于橋梁原創(chuàng)性的建筑

51、觀念,其中就包括使用斜拉橋系統(tǒng)。這個概念曾經(jīng)被市政府批準,但是由于財政問題,這個設計在重新恢復之前曾經(jīng)被暫停了七年。</p><p>  2003年,該項目被列入目標工程和方案設計工作,開發(fā)設計招標正式公布。這項工作又一次被授予了JSC研究所。重建計劃在2007年底完成并且被國家審查委員會積極地接收;建設工作就在當年年底開始。</p><p>  在進行技術可行性和經(jīng)濟適用性比較的基礎上,

52、大橋的結構概念獲得了認可。一個主要的限制是橋梁上部結構高度的嚴格限制。一方面,為了通航,橋梁必須保持一定的橋下凈空,另一方面,橋面高度又被拉扎列夫海軍上將限制,為了保護文物 ,橋面高度不能提高。</p><p>  為了滿足這些幾乎是相互矛盾的條件,橋面縱向剖面的曲線半徑只能為1000m,只有這樣才能滿足所有的條件。但是即使采用了這種最小的剖面半徑,關于橋面高度的苛刻要求使得橋面的最大高度只能為1.4m。這個條件

53、可以通過一個經(jīng)典的五跨連續(xù)梁或者斜拉索體系來解決。這兩個方案的費用幾乎相同,但是斜拉橋的方案更被看好,因為從建筑外觀來看它更有吸引力。另外一個好處是,它可以減少施工時間,因為沒有必要將橋墩建在河床上。</p><p>  這種非常規(guī)的外形結構,特別塔的形狀和它的不對稱的單跨布局,對來自JSC 研究所的工程師的設計能力提出要求,要求他們處理非標準的問題。其中一個問題是,必須為路面提供必要的剛度,同時最大限度地減少塔

54、基礎的重量和維持系統(tǒng)平衡。</p><p>  因此在施工中,一個行車道鋼塔選用單跨斜拉橋鋼橋面和正交異性板。路面用兩排柱子支撐,每排5個。纜繩線通過塔,并用鋼筋混凝土板錨固,這超出了Krestovsky的設計橋臺。前面的拱樓,傾向于河床,這意味著要用斜拉索和固定的錨板這種方式來承擔重量。這兩套的纜繩通過活動的斜拉橋鋼橋面和配重板進行固定。為了盡量減少甲板的總寬度,主要前表面梁的混凝土板被刪除。塔基礎的最佳受力分

55、布有拱形狀手段獲得,這樣在橋的橫截面更長。</p><p>  橋面上設有一個縱向的系統(tǒng)和橫向工字鋼正交異性板連接進行U形加勁。該加固點沿著橫向梁。在塔上,橋面進行堅固的加固,河堤取決于毛雷爾球面軸承。橋面的鋼部分是由10至15級低合金鋼構成(400MPa)</p><p>  這種纜繩每根是由50至73股VSL標準的繩索組成。每股的總長度大約31km。與此同時,路面是有2層40mm 和

56、50mm厚的瀝青混凝土鋪在Technoelastomost - S的膜防水層中。</p><p>  河岸基礎都是由高樁承臺鉆孔灌注樁深入含水層的堅定粘土中。上方的基礎,河堤是由現(xiàn)澆混凝土和花崗巖組成。</p><p>  橋梁施工由Mostootryad No 75實施,它是OAO的一個分支,同時,橋面鋼結構是由JSC Zavod Metallokonstruktsiy制造的,鋼塔結構則

57、是由NPO Mostovik制造的。</p><p>  為了更詳細設計,自動化研究所的專家編寫這個塔的復雜的三維模型和斜拉索錨固軟件用于分析報告。作為NPO Mostovik制造結構的基礎。使用這一成功專業(yè)建模使復雜的塔結構在相對較短的時間內(nèi)制造。</p><p>  考慮到大橋的建設時的一些外加的限制,JSC研究所建議在一份詳細的設計書上的修改。其中一項建議是用10級的低合金鋼更換塔上

58、纜繩的剛度。這樣可以鋼性固定在塔拱門和配重上。臨時的支撐在被安裝的路面上。</p><p>  這些修改可使后牽索建筑物得到很大程度的簡化,并且也會消除張拉這些纜索的必要,使纜索停留設置的時間減少了一半。</p><p>  另外,它還意味著只要橋上瀝青和混凝土鋪裝完畢,支持橋面的纜索可以一次張拉成功,分析包括從最長的一副纜索到最短一副纜索的張拉。除了拉力,橋面臨時支撐豎直方向的位移也得到

59、了控制。實際張拉工程進行的解決方案符合設計要求。如果有必要,每個階段的拉力和位移等數(shù)據(jù)再交給總承包商的設計師之前都需要更正的設計介紹。整體而言,計算得出的數(shù)據(jù)與實際參數(shù)是密切相關的</p><p>  事實上,總承包商用了17個月就完成了橋梁施工設計的全部工程。新的斜拉橋與周圍的景色和諧地融合到了一起。因為沒有在河床上設置橋墩,沿著馬來亞的景觀就可以開放了。拱塔作為島上一個象征性的標志,清晰地佇立著,與背后的天空

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