土木专业外语L.ppt

1,Lesson 10 Dam 水坝,New words and phrases: estuary auxiliary spillway evacuate silt reservoir reap profile monolithic buttress configuration strata(stratum的复数) permeability assess simultaneous equilibrium constituent expedient blend retard hydrate pulverize rockfill surface-active agent 表面活性剂 water-to-cement ratio 水灰比 embankment dam 堤坝,2,3. spillway 溢水口，泄洪道 spill+way spilln. v. 溢出、溅出 20. retard v. n. 延迟、阻止、妨碍 retard the progress/development of sth. 阻碍事物的发展 Lack of science and education retards social progress. 缺乏科学和教育会妨碍社会进步。,Words,3,Dam,A dam is a structure built across stream, river, or estuary to retain water. 一个水坝是横跨一条小溪、河流或港湾修建的用来储水的结构。 Its purposes are to meet demands for water for human consumption, irrigation, or industry; to reduce peak discharge of flood water; to increase available water stored for generating hydroelectric power; or to increase the depth of water in a river so as to improve navigation 它的用途是满足人类消费、灌溉或工业用水的需求；减少洪水的高峰流量；增加供水力发电用的可用的储存水的数量；或者增加河流水深以改善通航条件。 An incidental purpose can be to provide a lake for recreation 一个附带的用途是可以为娱乐消遣提供一个湖泊。,4,Dam,Auxiliary works at a dam may include spillways，gates，or valves to control the discharge of surplus water downstream from the dam；an intake structure conducting water to a power station or to canals，tunnels，or pipelines for more distant use；provision for evacuating silt carried into the reservoir；and means for permitting ships or fish to pass the dam 一个水坝的辅助工程可能包括控制从水坝出来的过多的下游水的排放的泄洪道，闸门，或者阀；引导水流到发电站或到运河、隧道或管道为更远距离的利用的一个进口结构；抽出被带进水库的淤泥的设备；以及允许轮船或鱼类通过大坝的一些手段。 A dam therefore is the central structure in a multipurpose scheme aiming at the conservation of water resources 因此，针对水资源保护问题，一个水坝在多目标方案中是中心结构。,5,Dam,The multipurpose dam holds special importance in the underdeveloped countries，where a small nation may reap enormous benefits in agriculture and industry from a single dam 多种用途的水坝在不发达的国家起着特别重要的作用，一个小国家在农业和工业方面可能从一个单个的水坝上获得巨大的利益。 Dams fall into several distinct classes，by profile and by building material 水坝根据其轮廓和建筑材料可以分为几个不同的级别。 The decision as to which type of dam be build depends largely on the foundation conditions in the valley and the construction materials available 决定修建那种类型的水坝很大程度上取决于流域的基础条件和可获得的建筑材料。,6,Dam,Basically，the choice of materials now lies between concrete，soils，and rockfill 基本上，现在材料的选择就在混凝土、土壤和填石当中。 Though a number of dams were built in the past of jointed masonry，this practice is now largely obsolete. 虽然在过去修建了大量的有接缝的石坝，但是现在这种方法在很大程度上被荒废了。 The monolithic form of concrete dams permits greater variations in profile，according to the extent water pressure is resisted by the deadweight of the structure，is transferred laterally to buttresses，or is carried by horizontal arching across the valley to abutments formed by the sides of the valley 整体浇铸式的混凝土大坝允许在外形上有更多的变化，由于长度范围的水压力可由结构自重抵抗，可侧向转移到扶壁上，或者由横跨沟谷的水平拱架传递到由沟谷两岸形成的桥台上。,7,Basic Problems in Dam Design 水坝设计中的基本问题,Most modern dams continue to be of two basic types：masonry (concrete) and embankment (earthfill) 大多数现代水坝一直用的两种基本类型：砖石类（混凝土）和堤坝（填土）。 Masonry dams are typically used to block streams running through narrow gorges, as in mountainous terrain；though such dams may be very high，the total amount of material required is limited 砖石大坝通常被用来阻挡流经狭窄的峡谷的河流，就像在山区地形中；虽然这类大坝可能非常高，但是要求的材料总量却是有限的。,8,Basic Problems in Dam Design 水坝设计中的基本问题,Embankment dams are preferred to control broad streams，where only a very large barrier，requiring a great volume of material，will suffice 堤坝更适合控制宽阔的河流，在这些地方有一个非常大的障碍物就足够了，这个大的障碍物需要大量的材料。 The choice of masonry or embankment and the precise design depend on the geology and configuration of the site，the functions of the dam，and cost factors. 砖石或填土的选择和精确的设计取决于现场的地质概况和构造，大坝的功能，以及成本因素。,9,Site investigation and testing 现场调查和测试,Investigation of a site for a dam includes sinking trial borings to determine the strata 大坝的现场调查包括沉入钻孔试验以确定岩层。 The borings are supplemented by shafts and tunnels which，because of their cost, must be used as sparingly as possible 钻孔可以由打井和挖坑道补充，后两种方法因为它们的成本较高，所以必须被尽可能节约地利用。 In the shafts and tunnels，tests can be made to measure strength，elasticity，permeability，and prevailing stresses in strata，with particular attention given to the properties of thin partings，or walls，between the more massive beds 在井和坑道中，可以做实验测量岩层的强度，弹性，透水性和主应力，同时要特别注意薄的部分，或在更结实的基床之间的似墙的地方的特性。,10,Site investigation and testing 现场调查和测试,The presence in groundwater of chemical solutions harmful to the materials to be used in the construction of the dam must be assessed 地下水中对大坝施工要用到的材料有害的化学溶液的存在必须进行评估。 Sources of construction materials need explorationAs dams continue to increase in height，the study of foundation conditions becomes increasingly critical 建筑材料的来源需要踏勘。随着大坝的高度不断地增加，基础条件的研究变得越来越重要了。 Model tests play a major part in the structural，seismic，and hydraulic design of dams. 模型试验在大坝的结构设计，地震设计和水力设计中起着重要的作用。,11,Site investigation and testing 现场调查和测试,Structural models are particularly useful in analysis of arch dams and in verifying analytical stress calculations. 结构模型在拱坝的分析和分析应力计算的检验中特别有用。 Various materials have been used for model tests；on some early tests for Hoover Dam，rubber was employed 在模型试验中已经使用了各种不同的材料；在胡佛大坝的一些早期试验中，还使用了橡胶。 The need for accurate reproduction of stress patterns in complex models is met by using material of low elasticity 在复杂的模型中应力模式的准确再现这种需要可以通过使用低弹性材料来满足。 In a sense，dams themselves are models for future design 在某种意义上，大坝本身就是未来设计的模型。,12,Hoover Dam,13,Site investigation and testing 现场调查和测试,The instruments built into them to record movements under load，strains within materials after construction，temperature and pressure changes，and other factors are installed primarily to study the performance of the structure and to warn of possible emergencies，but their value in confirming design assumptions is important 修建在大坝中记录荷载下的运动，以及施工、温度和压力变化后材料内部的应变，和其他因素的仪器被安装上主要是用来研究结构的性能和警告可能的紧急情况，但是它们在确定设计思想上的价值是很重要的。 The digital computer has permitted considerable advance in analytical methods of design 数字计算机已经容许在设计的分析方法上有相当大的进步。,14,Site investigation and testing 现场调查和测试,Its ability to handle a great volume of data and to solve large sets of simultaneous equations containing many variables has made practicable the method of Finite Element Analysis 它处理大量数据和解答多组包含许多变量的联立方程的能力使得有限元分析法是可行的。 In this method，a complicated structure is divided into a number of separate equilibrium conditions，and strains are rendered compatible，thus leading to a complete analysis of stress and strain distribution throughout the structure 在这种方法中，一个复杂的结构被分成了许多单独的平衡条件，应变被协调地实施，这样就得到了整个结构的应力应变分布的完整的分析。,15,Problems of materials 材料的问题,Each of the two basic dam materials，concrete and earth or rock fill，has a weakness that must be overcome by the proper design of the dam 大坝的两种基本材料（混凝土和填石或填土）中的每一种都有弱点，这个弱点必须通过大坝的适当的设计来克服。 Weaknesses of concrete 混凝土的弱点 Concrete is weak in tensile strength；that is，it can be pulled apart easily 混凝土的抗拉强度很弱；也就是说它很容易就会被拉开。,16,Weaknesses of concrete 混凝土的弱点,Concrete dams must therefore be designed to place minimum tensile strain on the dam and to make use of concretes great compressive strength，or ability to support vertical loads 因此，混凝土大坝必须被设计得只有很小的拉应变作用在大坝上，并且利用混凝土很大的抗压强度，或者支撑垂直荷载的能力。 The chief constituent of concrete，cement，shrinks as it sets and hardens，due to water absorption in the crystalline structure，to evaporation of water to the atmosphere，and to cooling from the higher temperatures reached when the chemical reactions in the cement are in progress during hydration 由于晶体结构内对水的吸收、水在空气中的蒸发和从水泥水化过程中产生的高温冷却，混凝土的主要成分水泥，在凝固和硬化时要收缩。,17,Weaknesses of concrete 混凝土的弱点,Because of the large volume of concrete in a dam，shrinkage presents a serious cracking hazard 因为一个大坝中要用大量的混凝土，所以收缩呈现出严重的破裂危险。 Various expedients are used to overcome the problemConcrete is usually cast in separate blocks of limited height 各种各样的方法被用来克服这个问题。混凝土通常是在单独的一定高度的木块中浇铸的。 Gaps may be left to permit heat losses and filled in laterLow-heat cements may be used; these are specially blended so that rates of heat evolution are retarded 先要留出缝隙以容许热量损失，然后再填上。可以使用低热水泥，专门把这些混和起来以便减缓热发展速度。,18,Weaknesses of concrete 混凝土的弱点,Cement content can be safely reduced in the interior concrete in the dam，in which strength and resistance to climatic and chemical deterioration are less important 在大坝中混凝土内部的水泥用量可以安全地减少，在混凝土内部，强度和抵抗气候和化学损坏的能力不太重要。 The cement content，and therefore the heat caused by hydrating，can also be reduced by using aggregate (the other major constituent of concrete) of larger stones 水泥含量和因此由水合作用导致的热还能通过使用更大块的石料（这是混凝土的另一个重要成分）减少。 Another expedient is to use other fine-grained materials，such as fly ash (pulverized fuel)，as filler，reducing the total cement volume in the concrete 另一种方法是使用其他的有细密纹理的材料，比如飞尘（被研成粉末的燃料），就像填充料，可减少混凝土中水泥的总量。,19,Weaknesses of concrete 混凝土的弱点,Another is to use certain additives，surface-active agents，and air-entraining agents that permit using a lower water-to-cement ratio in mixing the concrete 还有一种办法是使用某种添加剂，表面活性剂和空气夹带剂，这些添加剂允许在混凝土混和物中使用较低的水灰比。 Techniques used to speed the cooling process include replacing some of the water in the mix by ice，circulating water through pipes laid in the concrete，and extracting excess water from surfaces by vacuum 用来加速冷却过程的技术包括：用冰代替混合物中一部分水，通过放置在混凝土中的管道循环水，用真空装置吸出表面多余的水。,20,Weaknesses of earth and rock fill 填土和填石的弱点,Soils and rock fragments lack the strength of concrete，are much more permeable，and possess less resistance to deterioration and disturbance by flowing water 缺乏混凝土强度的土和岩块渗透性更大，并且抗流水损坏和干扰的能力差。 These disadvantages are compensated for by a much lower cost and by the ability of earth fill to adapt to deformation caused by movements in the dam foundation 这些缺点可以由更低的成本，以及填土能适应大坝基础的运动导致的变形的能力来补偿。 This assumes，of course，sufficient usable soil available close to the dam site 当然，这是假定在坝址附近有足够的可用的土壤。,21,Weaknesses of earth and rock fill 填土和填石的弱点,In bare mountain country it may be necessary to quarry rock and construct a rockfill rather than an earthfill dam 在山脉都光秃秃的国家，有必要开采岩石，修建一座填石坝而不是填土坝。 Earth fill is of course more economical，and often a suitable borrow area can be found close to the site 当然，填土是经济的，而且通常在坝址附近能找到合适的借土的地方。 Soil consists of solid particles with water and air in between 土壤由固体颗粒和水以及中间的空气组成。 When the soil is compressed by loading，as occurs in dam construction，some drainage of air and water takes place，causing an increase in pressures between the solid particles 当土壤受到荷载压力时，就像发生在大坝修建过程中，空气和水就会被排出，这样就会导致固体颗粒之间的压力增加。,22,Weaknesses of earth and rock fill 填土和填石的弱点,When there is a high rate of seepage，the soil tends to develop differential pressures and reach a condition called quick，in which it behaves as a fluid 当渗流速度很高时，土壤往往会产生不同的压力，达到一个被称为流动的状态，这时它表现出的特性就像流体。 Even if it does not reach this condition，there is often some weakening of its structure，and steps must be taken to counter this 即使它没有达到这种状态，通常它的结构已经很脆弱了，必须采取一些步骤来预防这种现象。,23,the Earthquake Problem 地震问题,Many large dams have been built in the seismically active regions of the world，including Japan，the western United States，New Zealand，the Himalayas，and the Middle East 许多已经修建的大型水坝都处于世界上的地震活动区，包括日本，美国西部，新西兰，喜马拉雅山脉和中东。 In 1968，the Tokachi earthquake damaged 93 dams in Honshu，the main Japanese Island；all were embankment dams of relatively small height 1968年，Tokachi地震毁坏了本州（日本最大的岛屿）的93座大坝；它们都是高度相对较矮的堤坝。 Despite a great deal of work on the distribution of seismic activity，the measurement of strong ground motions，and the response of dams to such motions，earthquake design of dams remains imprecise 尽管针对地震活动的分布、强地层运动的量测及水坝对这种运动的反应做了大量的工作，水坝的地震设计依然不够精确。,24,Tokachi earthquake,25,the Earthquake Problem 地震问题,The characteristics of strong ground motions at a given site cannot be predicted，and all types of dams possess some degree of freedom，imperfect elasticity，and imprecise damping 一个特定的地点的强地层运动的特征不能被预测，所有类型的水坝都具有一定的自由度，不完全的弹性和不精确的阻尼。 Nevertheless，the digital computer and model testing have given promise of considerable progress 然而，数字计算机和模型试验已经给这些方面带来了相当大的进步。 It is now possible to calculate the response of a concrete dam to any specified ground motion；this has been done for the Tang-e Soleyman Dam in Iran and the Hendrik Verwoerd Dam in South Africa 现在要计算混凝土大坝对任何特定的地层运动的反应已经成为可能； There has also been considerable advance in the theoretical estimation of the effects of ground motion on embankment dams 在地层运动对堤坝影响的理论评估方面也已经取得了相当大的进步。,26,the Tang-e Soleyman Dam,27,the Hendrik Verwoerd Dam,28,This text introduced the definition, the components and types of dams. We can also learn some basic problems in dam design, such as site investigation and testing, problems of materials and the earthquake problem from this text. 这篇文章介绍了水坝的定义，组成部分和类型。我们还可以从文章中了解到水坝设计过程中的一些基本问题，比如现场调查和试验，材料的问题，以及地震的问题。 要求：掌握本课介绍的专业知识和翻译方法。,Brief Summary,29,Lesson 11 Highway Engineering 公路工程,New words and phrases: abutting specdlative traverse benefit recreational logically gradation expressway compact accommodate frequency caliche oyster bituminous catchbasin adverse precipitation photogrammetric outlet barrier pneunatic-tired roller 汽胎压路机 public utilities 公共设施 calcium chloride 氯化钙 guard rail 护栏，护轨,30,Words,1. abutting 毗连的，邻接的 如：abutting building 毗连建筑物 abutting joint 对接, 毗连接头 abutting lot 相邻地段 10. accommodate 供应，提供，容纳，适应 如：accommodate oneself to 使自己适应于 accommodate oneself to new conditions 适应新的情况 accommodate sb. with 向某人提供 16. adverse 相反的，不利的，敌对的，逆的 如：adverse altitude (跳伞)不利高度 adverse circumstances 逆境 adverse conditions 不利条件， 有害状态 adverse current 逆流,31,Highway Engineering,Highway engineering includes highway planning, location, design, and maintenance. 公路工程包括公路规划、定位、设计和维修。 Before the design and construction of a new highway or highway improvement can be undertaken, there must be general planning and consideration of financing. 在着手做一条新建公路或改建公路的设计和施工之前，必须做总体规划和资金考虑。 As part of general planning, it is decided what the traffic needs of the area will be for a considerable period, generally 20 years, and what construction will meet those needs. 作为总体规划的一部分，要决定：在相当长的时期内，通常是20年，该区域的交通需要；以及哪种施工可以满足这些需要。,32,Highway Engineering,To assess traffic needs the highway engineer collects and analyzes information about the physical features of existing facilities, the volume, distribution, and character of present traffic, and the changes to be expected in these factors. 为了确定交通需要，公路工程师收集和分析关于已有设施的物理特征，当前的交通量、交通分布和交通特性，以及在这些因素上要做的变化等信息。 The highway engineer must determine the most suitable location, layout, and capacity of the new routes and structures. 公路工程师必须确定最合适的位置、布局和新线新结构的通行能力。 Frequently, a preliminary line, or location, and several alternate routes are studied. 通常，要仔细考虑初步的线形，或定位，以及几条可选择的路线。,33,Highway Engineering,The detailed design is normally begun only when the preferred location has been chosen. 按惯例，只有当更好的线位被选择以后，才开始详细设计。 In selecting the best route, careful consideration is given to the traffic requirements, terrain to be traversed, value of land needed for the right-of-way, and estimated cost of construction for the various plans. 在选择最佳线路时，要仔细考虑交通需求、要经过的地形、道路用地所需土地的价值、以及不同方案的预估施工造价。 The photogrammetric method, which makes use of aerial photographs, is used extensively to indicate the character of the terrain on large projects, where it is most economical. 利用航空拍摄技术的摄影制图方法被广泛地利用起来显示大型工程的地形特征，在大型工程中采用这种方法是最经济的。,34,Highway Engineering,On small projects, ground-mapping methods are preferred. 对于小型工程，就宁可选择地面制图方法。 Financing considerations determine whether the project can be carried out at one time or whether construction must be in stages, with each stage initiated as funds become available. 资金方面的考虑决定着工程是否能一次实施或者必须分阶段施工，每个阶段都只有当可以获得资金的时候才开工。 In deciding the best method of financing the work, the engineer makes an analysis of whom it will benefit. 在确定为工程集资的最好的方法的过程中，工程师要分析工程将对谁有利。 Important highways and streets benefit, in varying degrees, three groups: users, owners of adjacent property, and the general public. 重要的公路和街道在不同程度上对三组人群有利：使用者、邻近房产的所有者、以及全体公众。,35,Highway Engineering,Users of improved highways benefit from decreased cost of transportation, greater travel comfort, increased safety, and saving of time. 改善了的公路的使用者从减少的运输成本、更舒适的旅行、增加的安全感、和节约时间中得到好处。 They also obtain recreational and educational benefits. 他们还可以获得消遣和教育的好处。 Owners of abutting or adjacent property may benefit from better access, increased property value, more effective police and fire protection, improved street parking, greater pedestrian traffic safety, and the use of the street right-of-way for the location of public utilities, such as water lines and sewers. 邻近房产的所有者可以从更好的接近机会、增加的房价、更高效的治安和防火、改善的街道草坪、更安全的行人交通、和公众设施位置街道优先权的使用，比如水管和污水管这些方面获得利益。,36,Highway Engineering,Evaluation of various benefits from highway construction is often difficult but is a most important phase of highway engineering. 从公路建设中获取不同利益的评价通常是公路工程中很难但又是最重要的一个阶段。 Some benefits can be measured with accuracy, but the evaluation of others is more speculative. 一些利益能够精确地推测出来，而另一些就显得更投机了。 As a result numerous methods are used to finance construction, and much engineering work may be involved in selecting the best procedure. 结果，许多的方法就被用来为建设集资，很多的工程项目可能就牵涉到选择最佳做法。,37,Environmental evaluation 环境评价,The environmental impact of constructing highways has received increased attention and importance. 修建公路对环境的影响已经受到了越来越多的注意和重视。 Many projects have been delayed and numerous others canceled because of environmental problems. 许多工程已经被推迟，其他的很多已经被取消，就是因为环境问题。 The environmental study or report covers many factors, including noise generation, air pollution, disturbance of areas traversed, destruction of existing housing, and possible alternate routes. 环境研究或报告包括了许多因素：噪音的产生、空气污染、对被穿过区域的干扰、原有房屋的毁坏、和可能供选择的线路。,38,Right-of-way acquisition 道路用地的获得,Highway engineers must also assist in the acquisition of right-of-way needed for new highway facilities. 公路工程师还必须协助新的公路设施所需的道路用地的获得。 Acquisition of the land required for construction of expressways leading into the central business areas of cities has proved extremely difficult； 实践证明，要取得建设通向城市商业区高速公路所需的土地非常困难； the public is demanding that traffic engineers work closely with city planners, archit