土木工程专业英语第二版(段兵延)Lesson14

1、how tunnels are built如何开挖隧道after the general direction for a tunnel has been determined, the next steps are a geological survey of the site and a series of borings to obtain specific informeition on the strata through which the tunnel may pass the length and cross section of a tunnel generally arc g

2、overned by the use for which it is intended , but its shape must be designed to provide the best resistance to internal and external forces . generally , a circular or nearly circular shape is chosen.在一条隧道的大致方向定下来之后，下一步就是调查隧道沿途地层的钻孔资料并获取具体的 地层信息。隧道长度和横断面通常由其用途决定，但是其形状必须设计成对内外荷载产生最 佳抗力的形式。通常会选择圆形或近似的

3、圆形。in very hard rock , excavation usually is accomplished by drilling and blasting . in soft to medium-hard rock , a tunnel-boring machine typically does the excavating work . tn soft ground , excavation usual 1y is accomplished by digging or by advancing a shield and squeezing the soft material int

4、o the tunnel. in underwater tunneling , a shield is used to advance the work .another method of building an underwater tunnel is to sink tubular sections into a trench dug at the bottom of a river or other body of water.在非常坚硬的岩石中，通常采用钻机和爆破廿挖。在软弱到中硬岩石，采用隧道挖掘机是典 型的开挖方式。在软弱土层，通常采用盾构和挤压软弱土质的方式向前推进。在所有岩石

5、或 土层的开挖方式中，淤泥土要被收集起来运出隧道。在开挖水下隧道吋，要采用盾构向前推 进。另一种开挖水下隧道的方法是将深管放入河底或水中其他位置的已开挖的深沟中。hard-rock tunneling short turrncis through hard rock arc driven only from the portals , but longer ones usually are driven also from one or more intermediate shafts some long tunnels have been buiit with the aid of a sm

6、all pilot tunnel driven parallel to the main tunnel and connected with it by crosscuts at intervals . the pilot tunnel not only furnishes additional points of access but also a route for removing muck and for ventilation ducts and drainage line.硬岩隧道 穿过硕岩石短隧道仅从入口开挖，但是较长的隧道通常是从一个或几个地方同时开挖。有些 长隧道是在平行于主

7、隧道开挖的小型导洞辅助下建造的。导洞与主隧道z间每隔一段距离由 横巷连通。导洞不仅是通道的附属设施也是运土，通风，排水的通路。another method is the heading-and-bench system , formerly used on most large tunnels because it required smaller amounts of powder and permitted simuitaneous drilling and mucking ( removal of excavated material). the upper portion of the

8、 tunnel is driven ahead of the lower part which is called the bench a separate crew is thus able to muck in the lower portion of the tunnel while the upper portion is being drilled .另一种方法是采用正台阶开掘系统，以前被用于大型隧道因为它仅要求更少的火药并且允许 同吋钻孔和运土(转移开挖材料)上部隧道导向下部一这就叫做阶地，一部分独立的施工 人员就可以在上部钻孔的同时在下部运土。with improvemcn ts

9、 in tunneling met hods and mach in ery，the full-face method of attack , previously used only in small tunnels , came into common use in building large ones .this change was partly brought about by the jumbo , a movable platform on which numerous rock drills are mounted by this device , a 1 arge part

10、 of the turrnel，s face can be drilled at one time . the full-face method became the comm oncst and fas test way to drive a tunnel.随着隧道开挖方法的改善和机械化，以前仅用于小型隧道的全面施工方法，也开始普遍用于 修建大型隧道。这种改变部分原因是隧道钻车一一种装有大量岩石钻头的可移动平台的引 进。利用这种设备，一大片隧洞面可同时钻探。全面施工法已变成最普遍最迅速的开挖隧道 方法。soft-ground tunneling . some tunnels are driv

11、en wholly or mostly through soft material . in very soft ground , little or no blasting is necessary because the material is easily excavated .软土层隧道有一些隧道是全部或绝大部分穿越软土层。在很软的土层屮很少甚至不需要爆破，因为土质 非常容易开挖。at first , forepol ing was the only method for building tunnels through very soft ground . forepoles are

12、 heavy planks about 5 feet (1.5 meters ) long and sharpened to a point they were inserted over the top horizontal bar of the bracing at the face of the tunnel the forepoles were then driven into the ground of the face with an outward inclination after all the roof poles were driven for about half of

13、 their length , a timber was laid across their exposed ends to counter any strain on the outer ends . the forcplcs thus provided an extension of the tunnel support , and the face was ext ended under t hem when the ends of the forepoles were reached , new timbering support was added , and the forepol

14、es were driven into the ground for the next advance of the tiirmel ing .during excavation until timbering or other support was erected.一开始，超前伸梁掘进法是在软弱土层屮建造隧道的唯一方法。超前掘进伸梁是一块人约5 英尺(1.5m)长并且前端被锐化成一点的重重的厚板。他们被插入隧道表面的支撑柱的顶 层水平条内。然后超前伸梁向外倾斜钻入土层表面，在所有顶层杆被插入一半深度后，一根 木料被交叉放置在它们的外露端来抵抗所有的外部应变。仲梁就这样提供了一种可以仲缩的

15、坑道支撐，表面在其下伸出来。当杆的末端伸到后，再添加新的木材，伸梁被插入土中供隧 道下一节使用。the use of compressed air simplified working in soft ground. an airlock was built, though which men and equipment passed, and sufficient air pressure was maintained at the tunnel face to hold the ground firm during excavation until timbering or other s

16、upport was erected 压缩空气的使用简化了软土中的施工。首先建成一个空气锁，人和设备通过它进出，在开挖 过程中，足够的空气压力來维持坑道表面的坚固直至木材或其他支撑设施树起來。another development was the use of hydraulically powered shields behind which cast-iron or steel plates were placed on the circumferenee of the tunnels. these plates provided sufficient support for the tu

17、nnel while the work proceeded, as well as full working space for men in the tunnel 另一种发展是以铸铁或钢铁圆盘嵌固隧道四周其后以水压力盾构支撑。这种铁盘在施工过程 屮为隧道提供了足够的支撐力，同样为施工人员提供了足够的施工空间。underwater tunneling .the most difficult tunneling is that undertaken at considerable de pths below a river or other boby of watern such cases,

18、water seeps through porous material or crevices ,subjecting the work in progress to the pressure of the water above the tunneling path.when the tunnel is driven through stiff clay, the flow of water may be small enough to be removed by pumpingnmore porous ground,compressed air must be used to exclud

19、e water. the amount of air pressure that is needed increases as the depth of the tunnel in creases below the surface 水下隧道施工最困难的隧道是在一条河的下面一左深度处或水域其他部分屮开挖隧道。在这种情况下, 水会通过可渗透材料或裂缝渗出，影响了在上部水压力作用下的隧道施工进度。当隧道穿越 粘稠土质时，水的流量也许会小到用水泵就可以抽干。在更大渗透性的土壤屮，必须使用压 缩空气來排水。所需空气压力随隧道距离表层的距离增加而增加。a circular shield has prov

20、ed to be most efficient in resisting the pressure of soft gro und,so most shield-driven tunnels are circular.the shield once consisted of steel plates and angle supports,witha heavily braced diaphragm across its face.the diaphragm had a number of opening with doors so that workers could excavate mat

21、erial in front of the shield. in a further development,the shield was shoved forward into the silty material of a riverbed , thereby squeezing displaced material through the doors and into the tun nel,from which the muck was removed.thecylindrical shell of the shield may extend se veral feet in fron

22、t of the diaphragm to provide a cutting edge.a rearsection,called thetail, extends for several feet behind the body of the shield to protect workerslarge shiel ds,an erector arm is used in the rear side of the shield to place the metal support seg merits along the circumference of the tunnel实践证明，圆形盾

23、构抵抗软土压力是最有效的，所以大多数盾构掘进的隧道都是圆形的。盾 构曾经是由钢盘和角撑组成，再加上前端一个很重的支撑隔层。前端隔层有许多开的门以便 工人可以在盾构前部开挖。在进一步的改进中，盾构向河床的粉质粘土中灌浆，通过这种方 式将软弱土质从门里挤压进隧道，再从隧道将土运出。柱状的盾构壳可以在隔层前伸长好儿 尺以提供一个剪切面。后面的部分被称为尾巴向后伸展好儿尺来保护施工工人。在大型的盾 构机械中，一个起重臂被用在盾构的尾部延隧道四周来代替金属支撑段。the pressure against the forward motion of a shield may exceed 1,000 po

24、unds per square foot (4,880kg/sq meter). hydraulic jacks are used to overcome this pressure and advanee the shield, producing a pressure of about 5,000 pounds per square foot(24,500k g/sq meter) on the outside surface of the shield 盾构向前移动的阻力可能超过1000磅/平方尺(4880公斤/平方米)。液压千斤顶被用來克 服这个阻力推动盾构向前，它能在盾构外侧提供每平

25、方尺5000磅压力(24, 500公斤/平方 米)shields can be steered by varying the thrust of the jacks from left side to right side or from top to bottom, thus varying the tunnel directi on left or right or up or dow n. the j acks shove against the tunnel lining for each forward shove. the cycle of operation is f orwar

26、d shove jine, muck, and then another forward shove the shield used about 1955 on the third tube of the lincoln tunnel in new york city was 18 feet (s.smeters) long and 31.5 feet (9.6meters) in diameter. it was moved ahead 32 inches (81.2cm) per shov e, permitting the fabrication of a 32-inch support

27、 ring behind it.盾构可以通过各种起重机左右上下调整，以适应隧道左右上下的方向。千斤顶延隧道线向每 一段向前的装炉内挤浆。整个循环过程是向前推进，定线，运土，然后另一段向前推进。1 955年用于纽约市林肯隧道第三段的盾构长18尺(5.5米)直径31.5尺(9.6米)。每次 向前推进32英寸(81.2cm),在其后制作一个32英寸的支撑环。铸铁段通常被用在这样的盾构后面。它们被立起来并在短时间内熔为一体以提供强度和防水。 在林肯隧道的第三节，每段7尺（2m）长，32英寸（81cm）宽，14英寸（35.5cm）厚， 重大约15吨。这些段由14个小片段环熔合在一起。这种熔合的加紧先由手

28、工后由机器完 成。一旦它们就位，这些片段被旱在一起以保证永久性防水。sunken-tube tunnels. where the riverbed subsoil is firm and the river current is not exc essive,shore-fabricated tunnel sections can be towed over a prepared trench in the river bottom and suck into place to form a underwater tunnel. the first major prefabricated,fl

29、 oated,and sun ken tunnel was the detroit river tunnel betwee n detroit and win dsor,o nta rio.this vehicular tunnel was built in 1906-1910 the next important vehicular tunnel buil t by this method was the posey tube ,which was completed in 1928t runs under a sal twater arm betwee n oakland and alam

30、eda,calif. si nee then many other sunken-tube tunne is have bee n built un der rivers and saltwater bo dies, no tbly the tran sbay tunnel betwee n oakland and san francisco.沉管隧道当河床心土很坚固并且河水水量当前不是很充足的时候,岸边制造的隧道段可以拉到一个河 床中已经進备好的壕沟里并沉入水底以形成-个水下隧道。第一个主要的预制漂浮式沉管隧 道是位于安大略省的底特律和windsor之i'可的底特律河隧道。这条运输隧

31、道建于1906191 0年。第二条类似方法建成的主要运输隧道是posey隧道，竣工于1928年。它位于加州的 奥克兰和alameda之间的一条咸水河中。从那以后许多其他水底隧道被建于水下或是咸水 区域中，特别是位于奥克兰和圣弗朗西思科的transbay隧道。the cyli ndrical tunnel secti ons usually are made of steel in an on shore yard,each secti on is about 300 feet(90 meters) long and 28to 48 feet (8,5-14.6 meters) in diameter. after the openings ateach end of a sevtion are