土木工程英文论文翻译—沉埋隧道工程对环境的影响.doc

1、沉埋隧道工程对环境的影响 沉埋隧道的特征一座沉埋隧道具有两项基本特征：它是某一地下结构场地的一部分，要在繁忙的交通条件下保证施工，而并不意味这个地区是被充分地利用了的。因此，施工空间是很宝贵的。 它基本上是一预制结构。 最终将安装在河流或运河底部位置的隧道管段是在其它地方以非常接近工厂条件的方式筑造的，这种条件在现场和工地是不大可能达到的。施工规划上的优点和将管段制造与工地准备分开进行在后勤上的优点是显而易见的，还有极易于实现有效的质量控制的优点。 隧道工点在环境上的影响同样也大大少于隧道完全都在现场施工的情况；如像空间的需求和施工运输，这两个问题就大大的缓和。 当然，这些优点的先决条件是有现

2、成的可用于管段制造的适宜工地。它必须满足一系列有关环境影响的条件。在如荷兰这类人口密集的国家里，要找到合适的工地很不容易，而且很显然，一旦选定一可用位置，可多次使用就相当引人。因此，隧道施工的总体规划是一个供讨论的普通主题。 两端的地下结构一座新隧道连结到原来既有的地下结构中去，往往实际上是取代一既有的跨越水域的设施，如轮渡或桥梁。它也可为一既有隧道或桥梁的补充设施。无论决定建造一新隧道的理由如何，它的位置将在很大程度上受到既有地下结构布置的制约，而且其施工设计也要满足现有交通运输只受最小程度干扰的要求。这就意味着设计人员在隧道位置方面很少有选择的机会，因而不得不根据这一既定位置的条件和要求来

3、修改隧道设计。 这一情形主要影响连接隧道本身的引道部分。然而，因为引道由穿过含水地层的分段组成，就有可能要求用新的措施以控制引道建造基坑排水影响的范围。 引道沉埋隧道几乎总是位于沉积地带，在那里，隧道引道降到地下水位以下。在其完成时，它们是不透水的结构，周围的地下水不能渗入，存在的仅是单纯结构性质的环境影响。 然而在施工期间，环境问题则起着重要的作用。为了建造起结构物，必须开挖一施工基坑直至地下水位以下若干米的深处，传统施工方法要求在施工期中持续不断把水排干。除非采取进一步的措施，否则排水势必降低周围地区的水位，而且会导致一系列不希望的后果。沉陷将发生，周围楼房和建筑物的基础将受到影响，而且甚

4、至深桩基础也将受到沉陷土体经磨擦传递至桩上的额外向下荷载。由于沉陷而堤坝高程下沉，而且农业地区的排水水位将会受到影响。 还有可能造成一种性质完全不同的环境问题：施工区域内的泥土可能被污染。在这种情况下，施工基坑的开挖就要求格外注意，而且如有可能，就要采用诸如将泥土与水混合后经管道水力输送的特别方法。还必须有一个经批准能容纳被污染泥土的地方。 必须采取若干措施以防止由于抽、排水而造成被污染泥土迅速分布到大面积地面上。 在技术上，总是可能消除这些各种各样的影响。然而，由于做起来极为复杂而且会花费大量资金和时间，因此，目前倾向于寻找尽最大可能在水下建造引道和隧道进口的方法。最理想的是，排空施工基坑中

5、的水应该是一排干整个引道又完全不影响周围地下水位的单项作业。 明显的结论就是尽可能将施工基坑设计成最终产品的一部分。 引道边墙可设计成像有不透水芯墙的堤坝，其形式有泥浆墙、塑料板围幕或是常见的钢钣桩墙。对最后一种形式增加其挡土的功能，就可节省有价值的空间，而且可容易地达到在水下与不透水底板的连接。 底板可以用水下混凝土建成。这种方法已发展到能控制其高程和表面平整，以致达到在引道完全排干以后，只需要较少的修整工作。 另一种方法是采用不透水的塑料板材，加镇重安放于水下以盖住基坑底部和边坡。在荷兰，这种方法不仅用于隧道的引道，而且用于公络的凹槽段。 使用大面积的塑料板材，以泥土作镇重安放到水下，用在

6、一主要公路交叉口起到了长期的良好效果，它表明此技术已经推广使用。不久，荷兰的隧道引道可能会向人们展示有茂盛的绿色边坡，从而取代了灰色的混凝土竖墙。 引道也可在别处预制并以浮运构件的形式安装。此种方法只需用疏浚船开挖沟槽而完全不必排水。不过目前还没有能充分处理浮力作用和基础问题的适宜设计。 管段制造上述对地下水与引道开挖之间的关系的讨论大部分都可以同样的方式应用于制造管段临时场地的开挖。昂贵的解决办法给工程带来不合理的负担。而且，这个制造管段的场地必须多次被附近的开阔水域淹没并打开以使预制成的隧道管段运至船坞处以便为另一些管段让出地方。很少会有足够大的地方可供一次制造所有的管段。 总之，由于选择

7、制造管段船坞的位置不像选择隧道引道的位置那样要严格地用功能要求来决定，故选择制造管段船坞的位置具有可以灵活的优点。因此，制造船坞也就可以允许使用传统的排水法，如果由于上面列出的理由认为不允许使用传统的排水法时，而船坞又不得不与周围地下水分隔开时，这种地方使用不透水塑料板法由于其费用低就具有明显的优点。 另一种不影响周围地下水位的排水方法是抽水回灌法此法乃将渗入基坑的水用泵排出，又用泵将这些水通过过滤井管回灌到水的来源区。只要渗透速度不是太大而且可保持大致是个常数，这个排、灌时闭路循环就可以保持。这个新的措施，现在正用在荷兰的一个扩大的引道施工坑，由于这个基坑又要作为制造管段的船坞故加以扩大。

8、基槽的建造沉埋隧道的构槽是用疏浚法开挖的。在本文中，我们只强调用疏浚法开挖基槽的要求能达到极高的精确度，而且这个要求将决定最适合这一工作设备的类型。鉴于严格的定位容差，最好采用锚定疏浚船或在定位桩上的疏浚设备。不过，由于它们不能自由移动，就可能成为船只航运的障碍。 假如在浚挖区域有水流或浪潮的影响，浚挖的基槽就会成为水流携带或沿河底推移的沉积物的积存处。如果基槽开挖后长期不放置管段，就会很快形成淤积。在上述情况下，基槽开挖和隧道管段安装两工序的相隔时间必须越短越好，因而对这两道工序的安排都需格外准确，可以采用一种专门的设备于安装管段之前清理基槽。在荷兰，这种操作目前已发展到用在东斯格尔迪特防风

9、暴海浪堤坝的墩柱安装中达到很高精度。 疏浚搅起了河底沉积物，造成在一定时间一定区域的河水浑浊。最终这些成为悬浮的细颗粒物质会散开并重新逐渐沉淀下来。尽管这一过程对环境的影响有限，而且无害，但在一定范围内还是日益受到强烈的抨击。 如果要浚挖的泥土是已被污染的，事情就更为复杂化，因为在这种条件下，浚挖作业就会使污染扩散。现在浚挖技术已发展到通过使用一种专门的汲泥头来消除这一影响。采用从浮船上下悬帘幕将浚挖区域与周围完全隔开的方法也可减少污染扩散。 在这一方面的进一步发展目前大家都注意到，在荷兰大部分水道底部都含有被污染的沉积物已很明显，因而浚挖这些泥土必然要承担一些特别的环境要求。 当前，这些要求

10、尚未统一形成，而是针对每一具体工程提出不同的要求。希望这种拖延关键技术发展的混乱局面能迅速得以解决。 根据污染的类型和程度，可将被污染泥土分为14类。对于浚挖泥土（包括浚挖过程中的工艺用水）的弃置都按分类受到严格的限制；尤其是3和4类泥土都必须与外界隔绝，而且在可能的情况下加以净化。 在鹿特丹地区，已建成了一座储放这些固体废物以及其它有害物质的中心堆集场。此外，第4类浚挖弃土被放在临时的较小的堆集点，待其被净化后再转放至别的隔离存放处。在没有这类设施的地方，就必须按浚挖工程建立这种堆放点。这一措施很明显需要做大量的工作。 管段的运输和安装疏浚工作和对航运的阻碍都是管段运输和安装带来的环境问题。

11、要打开管段制船坞和加深船坞与安装点之间航道的浅水域就需要浚挖作业。前面有关浚挖的一些论述也适用这一情况。 安装工序中有一特殊的方面有可能涉及隧道基槽的最后清理。为了使清理和安装两工序间隔时间缩至最短，在管段安放到其最终位置底部回填砂之前已成功地采用了射水法清理隧道管段基底。用强力射水把要清除的最后一层沉积物冲成悬浮物，随后被水流带走。 在管段离开制造船坞，锚泊在临时码头和离开临时码头，浮运至安装点以及安装期间都有可能阻碍航运。只有最后一道工序才会造成航运在短期内临时完全中断或部分中断。 在这个方面，一座沉埋隧道穿过一条河流与穿过一条运河存在着差别。在后一种情况下，由于没有水流影响，就使得在沉放

12、和安装用可更好地控制管段。这种控制上的有利，就允许沉埋管段隧道采用更长管段单元，但这必须有足够大的制造船坞。Buried tunnel project on the environment Characteristics of a Buried deeply buried tunnel tunnel has two fundamental characteristics: (1) It is part of an underground structure of the site, to ensure that heavy traffic conditions, construction, a

13、nd does not mean that this area is full use of The. Therefore, the construction space is very valuable. Will eventually be installed in the location of the river or canal bottom section of tunnel is very close in other areas to build manufacturing plants, ways, and this condition is unlikely in the

14、field and reached the site. The advantages of planning and construction of pipe manufacture and the site will be ready to separate from the logistical advantages are obvious, there are extremely easy to implement effective quality control advantages. Tunnel work site on the environmental impact is a

15、lso considerably less than the construction of the tunnel fully all the circumstances at the scene; such as space requirements and construction of transport, these two issues is greatly easing. Of course, a prerequisite for these benefits is a ready-made for pipe suitable site. It must meet the cond

16、itions for a series of environmental impact. In the Netherlands such as densely populated countries, to find a suitable site is not easy, but it is clear that once selected an available position, can be used repeatedly for quite a draw a crowd. Therefore, the overall plan for the tunnel construction

17、 is a common topic for discussion. Both ends of the structure of a new underground tunnel link to the original structure to the existing underground, often in fact across the waters to replace an existing facility, such as ferry or bridge. It can also be a complement existing facilities in tunnels o

18、r bridges. Whether the decision to build a new tunnel the reason, its location will be in large part by the constraints of existing underground structure layout, and its construction design must also meet the existing transport only by the requirements of minimal interference. This means that the lo

19、cation in the tunnel area designers rarely have a choice, and thus have the position according to the established conditions and requirements to modify the tunnel design. This situation mainly affects the approach roads connecting part of the tunnel itself. However, because the approach road through

20、 the water by the formation of sub-components, it may require new measures to control the approaches to the scope of the construction pit drainage impact. Buried Tunnel approach roads are almost always located in the deposition zone, where the tunnel approach road down to the groundwater level below

21、. At its completion, they are impervious structure, the surrounding water can not penetrate, theres just the nature of the environmental impact of a simple structure. However, during construction, environmental issues will play an important role. To build from the structures, construction of foundat

22、ion must be excavated until the water table following a number of meters deep, the traditional construction method requires the construction period in the continuous draining of the water. Unless further measures, or drainage will definitely lower the water level in the surrounding area, and will le

23、ad to a series of undesirable consequences. Subsidence will occur, based on the surrounding buildings and structures will be affected, and even deep pile foundation soil settlement will also be passed by the friction down to the pile on the extra load. Subsidence and elevation of the dam sinking, an

24、d agricultural drainage water will be affected. May also result in a completely different nature of environmental problems: the construction area may be contaminated soil. In this case, the construction of the excavation pit special attention to requirements and, if possible, should be used, such as

25、 soil mixed with water and water transport by pipeline, special methods. There must also be able to accommodate an approved place of contaminated soil. Number of measures must be taken to prevent the pumping of contaminated water caused by the rapid distribution of the soil to a large area on the gr

26、ound. Technically speaking, is always possible to eliminate the impact of these kinds. However, it is extremely complex and do take a lot of money and time, therefore, tend to look at present the greatest extent possible the construction of approach roads and tunnels in the water imported methods. I

27、deally, the empty pit in the construction of a drainage of water should be no impact on the approach roads and the surrounding groundwater single operation. The obvious conclusion is that as far as possible the construction pit designed as part of the final product. Approach a wall can be designed t

28、o image the wall of the dam impervious core in the form of a slurry wall, curtain or plastic sheet of steel sheet pile walls common. On the final form (steel sheet pile wall) (off panel through the use of heavy anchor piles and soil) to increase its retaining function, you can save valuable space an

29、d can be easily achieved in the water and impermeable floor connection. Water under the concrete floor can be built. This approach has been developed to control the elevation and surface roughness, which completely drained to the approach road after finishing requires less work. Another method is th

30、e use of impermeable plastic sheet, add water to the town of emphasis placed on the bottom and cover the pit slope. In the Netherlands, this approach not only for the tunnel approaches, and the groove for the public network segment. Use large plastic sheet, to the soil to the water for the town re-p

31、laced by a major highway intersection in the play a long-term good results, it shows that this technology has been widely used. Soon, the Netherlands, the tunnel approach roads may be to show a lush green slope, thereby replacing the gray concrete vertical wall. Approach can also be prefabricated el

32、sewhere and in the form of installation of floating structures. This method only with trench excavation and dredging vessels do not have to drain. But not yet able to adequately address basic problems of buoyancy and appropriate design. Buried tunnel project on the environment Pipe manufacturing app

33、roaches to the excavation of underground water and the discussion of the relationship between the way the majority can be used to produce the same pipe excavation of the temporary venues. Expensive solution to bring an unreasonable burden to the project. Moreover, the manufacture of pipe near the si

34、te have repeatedly flooded the open waters and open to the precast tunnel segments into the transportation to the dock at the other pipe section in order to make room. Rarely a large enough place for all of the pipe manufacturer. In short, the choice of the location of manufacturing pipe dock not ch

35、osen as the location of the tunnel approach roads to be strictly determined by functional requirements, so choose the location of manufacturing pipe dock with the advantages of flexibility. Therefore, the manufacture of docks will be allowed to use the traditional water method, if the reasons listed

36、 above that do not allow the use of traditional water law, and the dock had to separate from the surrounding water, this places impermeable plastic plate because of its low cost to have obvious advantages. Another does not affect the drainage around the water table is pumping recharge Law This law i

37、s the foundation of the water into the pump discharge and pump water through the filter of these tube wells to the water source recharge area. As long as the penetration rate is not too large and can be maintained roughly a constant, the row, when the closed-loop irrigation can be maintained. The ne

38、w measures, now being expanded in the Netherlands approaches to the construction of a pit, but also because the foundation of the dock as the manufacture of pipe it to be expanded. Construction of foundation trench trough structure deeply buried tunnel excavation method is dredging. In this paper, w

39、e only stress the importance of dredging requirements of foundation trench excavation method can achieve high accuracy, and this requires that the work will determine the most suitable type of device. Given the strict positioning tolerances, preferably dredging boat anchor or pile in positioning the

40、 dredging equipment. However, because they can not move freely, it could become an obstacle to shipping vessels. If there is water in the dredging area, or the wave of the impact of dredging will become the base slot to carry water along the bottom or sediment accumulation over the place. If the fou

41、ndation trench excavation in place pipe for long periods, it will soon form a deposition. In these circumstances, the base section of tank excavation and tunnel installation of the interval between the two processes must be as short as possible, and thus the arrangement of the two procedure are to b

42、e particularly accurate, you can use a special device to clean the base before the installation of pipe slot. In the Netherlands, this operation has been developed to be used in the East (Eastern Scheldt) anti-dam pier storm waves reach a very high precision installation. Dredging stir up the river

43、sediments, resulting in a certain time a certain area of the water turbidity. Eventually become a suspended fine particles of these substances will spread out and gradually settle down again. Although this process had limited impact on the environment, and harmless, but in a certain range or the inc

44、reasingly strong criticism. If you want to have dredged soil is contaminated, it is even more complicated, because in such conditions, the dredging operation will cause the spread of contamination. Dredging technology has now developed to the drain by using a special mud head to eliminate this effec

45、t. Under the floating boat by hanging curtains from the dredging area will be completely separated from the surrounding method may also reduce the spread of pollution. Further development in this regard we have taken note of the current, most waterways in the Netherlands contain contaminated bottom

46、sediments have been very clear, so dredging the mud is bound to take some special environmental requirements. Currently, these requirements have not been unified to form, but made different for each specific project requirements. Hope that this delay in the development of key technologies of the cha

47、os can be quickly resolved. According to the type and extent of contamination, contaminated soil can be divided into 1 to 4 classes. For dredging mud (including dredging process water in the process) and disposal are subject to strict restrictions by category; particular, 3 and 4 the soil must be is

48、olated, and in possible to be purified. In the Rotterdam area, has built a store of these solid waste and other hazardous substances the center of the dump site. In addition, Type 4 is placed in temporary dredging spoil heap smaller point, let it be purified and then transferred to another isolated place repository. Place in the absence of such facilities to be established by dredging this dump sites. This measure is a clear need to do a lot of work. Transportation and installation of pipe wor