土木工程专业英语第四章

1、每节英语Youth is not a time of life, it is a state of mind.青春不是一段年华，而是一种心境。 Unit 4 Bridge Engineering本章内容1、Words and Expressions2、Translating: Bridge Engineering3、Translating skill and exerciseUnit 4 Bridge EngineeringUnit 4 Bridge Engineering本次课主要内容本次课主要内容 1、Unit 4 words and expressions 2、 Sentences tr

2、anslation Unit 4 Bridge Engineering1、Words and Expressions（1）capacity kpst n. 容纳能力；能力；地位；生产力；地位 bearing capacity 承载能力 ; 承载力 ; 承重能力 ; 支持力（2）foremost fmst adj. 最重要的，主要的 adv. 首先；居于首位地（3）deteriorationd,trren n.恶化；退化；堕落 Unit 4 Bridge Engineering（4）compromise kmprmaz n. 妥协；和解；折中 vi. 妥协；让步 vt. 妥协；危害 compro

3、mise boundry 组合界面（5）site sat n. 地点；位置；场所 vt. 设置；为.选址 Construction Site 建筑工地 ; 施工现场 ; 工地 ; 建筑地盘 I was working as a foreman on a building site. 我在一个建筑工地当工头。 Unit 4 Bridge Engineering（6）envisage nvzd vt. 正视，面对；想象 Envisage Failure 正视失败 We envisage that large scale projects might require additional metho

4、ds; if so, they could reasonably be added to this class. 我们认为，大型项目可能还需要其他方法；如果是这样，完全可以将它们添加到此类中。（7）mentality mentlt n. 心态；智力；精神力；头脑作用 Mentality pressure 心理压力 Social Mentality 社会心态 mentality plan 思路规划 Unit 4 Bridge Engineering（8）specification spesfke()n n. 规范；说明书；详述 Performance Specification 性能规格 ; 性

5、能说明 ; 性能规范 ; 性能指标 technical specification技术规范；技术说明 design specification设计规范；设计规格；设计任务书；设计细节 Id like to buy some land and have a house built to my specification.我想买块地并按照我的要求建一座房子。 Unit 4 Bridge Engineering（9）span spn n. 跨度；跨距；范围 vt. 跨越；持续；以手指测量 main span 主跨 side span 边跨 ; 旁跨 ; 侧孔 central span 中跨距 ; 中

6、心跨距（10）girder gd n.主梁 simple supported girder 简支梁 compound girder 合成梁Unit 4 Bridge Engineering Main grider is one of the most important forced parts of large pressing machine. Its optimal design is a hard nonlinear optimization problem. 主梁是大型压力机的关键受力构件之一，其最优设计问题是一类很难求解的非线性规划问题。（11）pier p n.码头；窗间壁；桥墩

7、 bridge pier桥墩 pier foundation墩式地基，墩基础Unit 4 Bridge Engineering（12）delegate delgt vt.委派.为代表；把（工作、权利）委托给（下级） n.代表（13）according to 根据，按照（14）arch t n.弓形，拱形；拱门 adj.主要的 vt.拱起；成为弓形 parabolic arch 抛物线拱 arch stone 拱石 arch bridge拱形桥Unit 4 Bridge Engineering（15）transmit trnzmt vt.传输；传播；发射；遗传 vi.传输；发射信号（16）sal

8、ient selnt adj. 显著地；突出的；跳跃的 n.凸角；突出部分 salient point 折点 ; 凸点 ; 凸起点（17）fabrication fbrke()n n.制造；建造；装配 Fabrication parameter 制造参数 Fabrication procedure 制造工序 ; 制造流程Unit 4 Bridge Engineering（18）spandrel spndrl n.拱肩 spandrel beam 外墙托梁 spandrel wall 拱上侧墙 ; 拱腔墙 ; 窗肚墙 ; 拱肩墙 spandrel structure 拱上结构 ; 拱上布局（19

9、）tend 易于，往往会；倾向于（20）through-truss n.下承桁架Unit 4 Bridge EngineeringA bridge usually controls the capacity of a transportation system, and is the highest cost per mile of the system.桥通常控制着运输系统的运输能力，而且每英里成本在交通系统中是最高的。Unit 4 Bridge EngineeringBecause the bridge is the key element in the transportation sy

10、stem, balance must be achieved between handling future traffic volume and loads and the cost of a heavier and wider bridge structure.因为桥梁是交通系统的关键部分，必须实现未来交通量和载重量与更重更宽桥梁结构造价之间的平衡。Unit 4 Bridge EngineeringStrength must always be foremost, but so should measures to prevent deterioration.强度必须始终是最重要的，应该采

11、取措施防止其衰减。Unit 4 Bridge EngineeringThe designer of new bridge has control over these parameters and must take wise decisions so that capacity and cost are in the balance, and safety is not compromised.新桥梁的设计师控制着这些参数，必须做出最佳的决策，从而使性能与成本达到平衡，并且安全性不受损害。Unit 4 Bridge EngineeringOftentimes engineers deceiv

12、e themselves into believing that if they gather enough information about a bridge site and the traffic loads, the selection of a bridge type for that situation will be automatic.通常，工程师自信的认为如果他们收集了足够的有关桥址和交通荷载的信息，该种情况下桥型的选择是顺其自然的。Unit 4 Bridge EngineeringFurthermore the use of analysis/design softwar

13、e will complete the job. Unfortunately, or perhaps fortunately it is not the case.此外，分析/设计的软件的应用也将完成这项工作。但不幸的是，也许并没有这么幸运。Unit 4 Bridge EngineeringA bridge engineer must have three points in mind while working on a bridge project: （i） creative and aesthetic; （ii） analytical; （iii） technical and pract

14、ical.从事桥梁工程的工程师必须牢记三个要点：（1）创意与美感；（ii）善于分析；（三）技术与实践。每节英语No winter lasts forever; no spring skips its turn.冬去春来，周而复始。 Unit 4 Bridge EngineeringUnit 4 Bridge EngineeringSo as to give a realistic evaluation of the possibilities of the construction technique envisaged and the costs involved.从而对设想的施工技术的可能

15、性和涉及的相关费用做出切合实际的评价。Unit 4 Bridge EngineeringIf these three mentalities do not coexist in a single mind, they must always be present on terms of absolute equality in the group or team responsible for the design.如果这三种心态不在一个的头脑中共存，那也必须始终在内部绝对平等的小组或设计团队中存在。Unit 4 Bridge EngineeringThere are no equations

16、, no compute programs or design specifications that can make our bridges beautiful. It is an awareness of beauty on our part.没有公式，没有计算程序或设计规范，能够使我们的桥梁美观，这是人类自身对美的意识。Unit 4 Bridge EngineeringAesthetics must be a part of the bridge design program from the beginning. It cannot be added on at the end to

17、 make the bridge look nice. At that time, it is too late. 美学必须从一开始就作为桥梁设计的一部分。不能在设计结束时才增加美学设计来使桥梁看起来美观，到那时就太晚了。Unit 4 Bridge EngineeringFrom the beginning, the engineer must consider aesthetics in selection of spans, depth of girders, piers, and the relationship of one to another. It is a responsibi

18、lity that cannot be delegated. We must demand it of ourselves, because the public demands it of us.从一开始，工程师必须在跨径、梁高、桥墩的选择和彼此之间的关系上就考虑桥梁的美观。它是一种责任 ，不能被委派。我们必须要求自己完成，因为这是社会对我们的要求Unit 4 Bridge EngineeringThere are a number of ways in which to classify bridges. Bridges can be classified according to: (

19、i ) materials （concrete, steel or wood etc）; （ii）usage (pedestrian, highway, or railroad); （iii）span（short, medium, or long）;（iv）structural from （slabs, girder, truss, arch, suspension, or cable-stayed）.桥梁的分类方法有多种。可根据桥梁的材料（混凝土桥、钢桥或木桥等）、用途（人行桥、公路桥、铁路桥）、跨径（小桥、中桥或大桥）、结构形式（板桥、梁桥、桁架桥、拱桥、吊桥、斜拉桥）进行分类Unit 4

20、 Bridge EngineeringThey all seem to contain parts of one another within each other. It is however suitable to classify bridges according to the location of the main structural elements relative to the surface on which the user travels, that is, whether the main structure is below, above, or coincide

21、s with the deck line. 他们彼此都包含对方的一部分。然而，根据主要结构单元与桥面的相对位置对桥梁进行分类是适当的，也就是说，主要看桥梁的主要结构是在桥面的下面、上面或与其齐平。每节英语Let life be beautiful like summer flowers and death like autumn leaves.愿生如夏花之绚烂，死如秋叶之静美。 Unit 4 Bridge EngineeringUnit 4 Bridge Engineering本次课主要内容本次课主要内容1、Unit 4 Words and Expressions 2、Sentences tr

22、anslation Unit 4 Bridge Engineering（1）anchorage k()rd n.锚地；下锚；停泊税（2）be regarded as 被认为是，被当做是（3）longitudinal ln(d)tjudn()l adj. 纵向的；纵观的；经度的 longitudinal section 纵切面 ; 纵剖面 ; 纵切片 ; 纵截面 longitudinal stress 纵向应力 ; 纵应力 ; 轴向应力 longitudinal strength 纵向强度 ; 拉伸强度 longitudinal strain 纵向应变 ; 纵向变形 ; 线应变 ; longit

23、udinal fault 纵断层 ; 纵向断层 ; 又称纵断层 Unit 4 Bridge Engineering（4）led to 导致，引起（5）girder bridge 梁式桥（6）flange fln(d) n. 凸缘（7）retrofit retrft vt. 修整；改进；更新 n. 式样翻新；花样翻新 A retrofit may involve putting in new door jambs. 房子翻新可能需安装一些新的门框。 Unit 4 Bridge Engineering（8）chief engineer 总工程师（9）sealant silnt n. 保护层；密封剂

24、；填缝料； formation sealant 封堵剂 fluid sealant 液体密封剂（10）flex fleks vt. 折曲，使收缩 vi.弯曲；收缩 n. 屈曲 dynamic flex 动态扭曲 Unit 4 Bridge EngineeringArched and truss-arched bridges are include in the classification of main structure below the deck line. 拱桥和桁架拱桥归类于主要结构在桥面以下的桥梁。Unit 4 Bridge EngineeringExamples are the

25、 masonry arch, the concrete arch, the steel-truss arch, the steel deck truss, the rigid frame, and the inclined leg frame bridges. 例如：石拱桥，混凝土拱桥，钢桁架拱桥，钢桥面桁架桥，刚架桥和斜腿刚架桥。Unit 4 Bridge EngineeringWith the main structure below the deck line in the shape of an arch, gravity loads are transmitted to the su

26、pports primarily by axial compressive forces. 在拱桥中，由于主要结构在桥面以下，重力主要以轴向压力的形式传递到支承结构。Unit 4 Bridge EngineeringAt the supports, both vertical and horizontal reactions must be resisted. The arch can be solid or it can be a truss of various forms. 支承结构必须抵抗垂直和水平的反力。拱可以是实体的，也可以是各种形状的桁架。Unit 4 Bridge Engine

27、eringSalient features of arch type bridges are:The arch form is intended to reduce bending moments （and hence tensile stresses）in the superstructure and should be economical in material compared with an equivalent straight, simply supported girder or truss. 拱桥的显著特点：拱形结构有利于减少上部结构的弯矩(减小拉应力),同时所用材料应当比采

28、用直线型的简支梁或桁架经济。Unit 4 Bridge EngineeringThe efficiency is achieved by providing horizontal reactions to the arch rib. If these are external reactions, they can be supplied at reasonable cost only if the site is suitable. 通过提高作用于拱肋的水平力可获得拱肋的承载能力。如果这些水平力是外部作用，只有桥址条件合适时，利用外部水平力才是合理的。Unit 4 Bridge Engine

29、eringThe most suitable site for this form of structure is a valley, with the arch foundation located on dry rock slopes. 拱桥最适合的位置是山谷，将拱桥基础置于干燥岩石斜坡上。Unit 4 Bridge EngineeringThe conventional curved arch rib may have high fabrication and erection costs, although these may be controlled by skilled labo

30、r. 传统的曲线形拱肋制作和安装成本高，尽管这些可以通过熟练的劳动力得以控制。Unit 4 Bridge EngineeringThe arch is predominantly a compression structure. For example, the open spandrel arch with the rib below the deck consists of deck, spandrel columns, and arch rib. 拱是以受压为主的结构。例如，拱肋在桥面以下的空腹式拱桥是由桥面、拱上立柱和拱肋组成的。Unit 4 Bridge EngineeringThe

31、 design must include accurate estimates of buckling and should be detailed so as to avoid excessive reduction in allowable stress. 设计时必须准确而详细地估计变形，从而避免过度降低容许应力。Unit 4 Bridge EngineeringThe classic arch from tends to favor concrete as a construction material. 经典拱桥倾向于用混凝土作为建筑材料。Unit 4 Bridge Engineeri

32、ngThe arch rib is usually shaped to take dead load without bending moments. This load is then called the form load. If the form load is large, the live load becomes essentially a small disturbance applied to a compressed member. 拱肋通常适合承受不产生弯矩的恒载。这种荷载被称为负载。如果负载很大，活载基本上就变成一种施加到受压构件的很小的扰动。Unit 4 Bridge

33、 EngineeringThe conventional arch has two moments resisting components-the deck and the arch rib. 传统的拱桥有两个抵抗力矩的构件桥面和拱肋。Unit 4 Bridge EngineeringUndesirable and unanticipated distributions of moment may occur, particularly in regions where the spandrel columns are short, normally near the crown of th

34、e arch, which may be avoided by careful detailing; for example by using pin ended columns. 在拱上立柱较短、靠近拱顶的区域，可能出现不理想的、预料不到的弯矩，这一点可以通过详细的设计加以避免。例如采用栓端柱。Unit 4 Bridge EngineeringSuspension, cable-stayed, and through-truss bridges are included in this category of main structure above the deck line. 吊桥，斜拉

35、桥，下承式桁架桥都归类于主要结构位于桥面上部的桥梁。Unit 4 Bridge EngineeringBoth suspension and cable-stayed bridges are tension structures whose cables are supported by towers. 悬索桥和斜拉桥都是索塔支承拉索的受拉结构。Unit 4 Bridge EngineeringSuspension bridges are constructed with two cables from which the deck, usually a stiffened truss is

36、hung by secondary cables. 悬索桥建有两根主索,加劲桁架梁通过吊索悬挂在主索上。Unit 4 Bridge EngineeringCable-stayed bridges have multiple cables that support the deck directly from the tower. 斜拉桥有多根直接锚固在塔柱上的斜索,支撑着桥面。Unit 4 Bridge EngineeringAnalysis of the cable forces in a suspension bridge must consider non-linear geometry

37、 due to large deflections, while linear elastic analysis is usually sufficient for cable-stayed bridges. 由于变形量较大，悬索桥索力分析时必须（通常）考虑几何非线性，而斜拉桥进行线弹性分析就足够了。每节英语Happiness takes no account of time. Cherish it.幸福年华似流水。且行且珍惜。 Unit 4 Bridge Engineering每节英语Nothing is impossible for a willing heart.心之所愿，无所不成。 U

38、nit 4 Bridge EngineeringUnit 4 Bridge EngineeringSalient features of suspension bridges:The major element of a stiffened suspension bridge is a flexible cable, shaped and supported in such a way that it can transfer the major loads to the towers and anchorages by direct tension. 吊桥的突出特点：吊桥的主要构件是柔性索，

39、它通过直接受拉将主要荷载传递给索塔和锚碇。Unit 4 Bridge EngineeringThis cable is commonly constructed from high strength wires. The deck is hung from the cable by hangers constructed of high strength wire ropes in tension这种索通常由高强度钢丝编制而成。桥面通过由高强度钢丝绳做成的受拉的吊索悬挂在主缆上Unit 4 Bridge EngineeringThis use of high strength steel in

40、 tension, primarily in the cables and secondarily in the hangers leads to an economical structure, particularly if the self-weight of the structure becomes significant, as in the case of long spans. 在主缆和吊索中对高强钢材抗拉能力的应用可使结构经济，特别是在自重大的大跨径桥梁中。Unit 4 Bridge EngineeringThe main cable is stiffened either

41、by a pair of stiffening trusses or by a system of girders at deck level. 主缆要么通过一对加劲桁架加强，要么通过桥面处的梁加强。Unit 4 Bridge EngineeringThis stiffening system serves to (i) control aerodynamic movements and (ii) limit local angle changes in the deck. It may be unnecessary in the cases where the load is great.

42、加劲系统的作用是：（1）控制空气动力作用，（2）限制桥面荷载角度的变化。在荷载很大的情况下，加劲系统可能就没有必要了。Unit 4 Bridge EngineeringIt is the only alternative of spans over 600m, and it is greatly regarded as competitive for span down to 300 m. 这是跨度大于600m时的唯一选择，同时跨度下降至300米时也同样被认为是极具竞争性的。Unit 4 Bridge EngineeringSalient features of cable-stayed br

43、idges:As compared with suspension bridges, the cables are straight rather than curved. As a result, the stiffness is greater. 斜拉桥的显著特点是：与悬索桥相比，斜索是直的而不是弯曲的。其结果是，斜拉桥的刚度大。Unit 4 Bridge EngineeringThe cables are anchored to the deck and cause compressive forces in the deck. 斜索锚固在桥面上，使桥面受力。Unit 4 Bridge

44、EngineeringCompared with the stiffened suspension bridge, the cable-braced bridge tends to be less efficient in supporting dead load, but more efficient in supporting live load. As a result it is not likely to be economical in the longest spans. 与加劲悬索桥相比，斜拉桥在支承静荷载方面不如悬索桥，但在支承活载方面比悬索桥更有效。因此，在特大跨径桥梁中，

45、斜拉桥可能是不经济的。Unit 4 Bridge EngineeringThe cables may be arranged in a single plane, at the longitudinal centerline of the deck.Aerodynamics instability has not found to be a problem in such structures. 拉索可沿着桥轴线方向布置在同一个平面内。在斜拉桥中还没有发现空气动力学不稳定性问题。Unit 4 Bridge EngineeringSalient features of through bridg

46、es:A bridges truss has two main structural advantages: (i) the primary member forces are axial loads; (ii ) the open web system permits the use of a greater overall depth than for an equivalent solid web girder. 下承式桥梁的显著特点：桁架具有两个主要的结构优点：（1）主要构件上的力是轴向力。（2）空腹式体系比同样的实腹梁利用的整体深度大。Unit 4 Bridge Engineerin

47、gBoth these factors lead to economy in material and a reduced dead weight. The increased depth also leads to reduced deflection, that is , a more rigid structure. 这两个特点使材料用量省，并减小自重。深度的提高能够降低偏移，也就是增大了结构的刚度。Unit 4 Bridge EngineeringEconomical for medium spans,Aesthetically pleasing. 对中等跨径的桥梁是经济的，美观。Unit 4 Bridge EngineeringGirder bridges (figure 4-1) of all types are include in the category of main structure coinciding with the deck line. Example are:在所有的分类中，梁桥归类于主要结构与桥面重合的类型。例如:Unit 4 Bridge EngineeringSlab (solid and voided)T-beamI-beam,Wide-