11 Chapter 11 Highway Engineering.pptx

第1页：第十一章道路工程

Chapter 11 Highway EngineeringSection A Highway Engineering

第2页：公路工程的内容

IntroductionHighway engineering includes highway planning, location,design, and maintenance.

公路工程包括规划、定线、设计和维护。

Before the design and construction of a new highway orhighway improvement can be undertaken, there must be generalplanning and consideration of financing.

在一条新建公路或者改建公路设计施工前，必须进行整体规划和资金考虑。

As part of general planning, it is decided what the traffic needsof the area will be for a considerable period, generally 20 years,and what construction will meet those need.

作为整体规划中的一部分，首先要确定相当一段时间内当地的交通需求，一般为20年，还有就是修建什么样的工程将会满足交通需求的需要。

第3页：公路定线的四个阶段

Highway LocationThe highway location process involves four phases: Officestudy of existing information、Reconnaissance survey、Preliminary location survey、Final location survey.

公路定线的过程一般包括四个阶段：现有资料室内研究、踏勘测量、初步定线、最终定线。

Traditionally, highway location practice has been fieldoriented([′ɔ:riənt]vt.定向，定位，使适应，使确定位置), that is,thebulk([bʌlk]n.湿胀性，主体) of the location party’s time andeffort went to measurement and observation “on the ground”.

传统的公路定线的做法都是在野外进行的，也就是说，定线工作要花大量的时间和精力在现场进行测量和观察。

第4页：路线方案的选择

Highway LocationThe first step towards fixing the road alignment is to take anoverall look at the area concerned, select what appear to bepossible routes between the terminal points, and then closelyexamine each of these in turn to decide which will be the mostsuitable, without actually determining the precise centre-line.

第一步，选定路线是要对相关地区进行全面审视的，在起终点间选择可能的路线，之后仔细考察每一个方案以决定最合适的路线，此时不需要确定准确的道路中心线位置。

第5页：踏勘测量

Highway LocationThis stage of the procedure is termed thereconnaissance([ri′kɔnisns]n.踏勘，勘察，侦察) survey and the form which ittakes depends to a great extend on whether or not large-scalecontoured([′kɔntuə]n.等高线，外形，轮廓)maps of the area arealready available.

这一阶段又被称为踏勘测量，踏勘采取的形式很大程度上依赖于该地区是否具有已经应用的大比例地形图。

第6页：比较路线与纵断面

Highway LocationBy inspecting these maps and drawinglongitudinal([lɔndʒi′tju:dinl]adj.经度的，纵向的)sections along possiblealignments([ə′lainmənt]n.线形，定线，排列成行), a number ofalternative routes can be considered, all of which must satisfy therequired engineering design standards for horizontal curveradii([′reidiai]n.（复数）半径)andgradients([′greidjənt]n.

坡度，梯度，斜率).通过审查这些地图和沿着可能的线向绘制纵断面可以考虑许多比较路线，所有这些路线必须符合工程设计标准要求的平曲线半径和坡度。

第7页：现场踏勘的目标

Highway LocationReconnaissance of the area was the first step; thelocator([ləu′keitə]n.定位器，探测器), using available topographicmaps and sometimes an airplane, explored the area.

现场踏勘是定线的第一步，之后就可以利用现有的地形图有时甚至利用飞机，用定位器对现场进行勘查。

His aim was to search out feasible routes and determine suchprimary controls as mountain passes or suitable river crossingsand to locate major obstacles such as steep slopes ormarshes([mɑ:ʃ]n.

沼泽，湿地).它的目标就是寻找可行的路线并确定基本的控制点，例如沿线的山脉、跨越的河流，以及找出主要的障碍，包括陡坡或沼泽。

第8页：公路定线的基本原则

Highway LocationThe basic principle for locating highways is that roadwayelements such ascurature([′kə:vətʃə]n.曲率，曲度)and grademust blend with each other to produce a system that provides forthe easy flow of traffic at the design capacity, while meetingdesigncriteria([krai′tiəriən]（pl-ria）n.指标，准则)and safetystandards.

定线的基本原则是车行道要素如曲度和坡度必须互相组合，在满足设计规范和安全标准的要求的同时，提供满足设计通行能力并且平稳的交通流体系。

第9页：环境与社会影响

Highway LocationThe highway should also cause a minimal disruption to historicandarcheological([′ɑ:kiə′lɔdʒikəl]adj.考古学的)sites and to otherland-use activities.

这条公路还应该对历史和考古遗迹以及其他土地利用活动造成的干扰最小化。

Environmental impact studies are therefore required in mostcases before a highway location is finally agreed upon.

在最终确定公路线路之前，大多数情况下还需要进行环境影响研究。

第10页：平面线形组成

Alignment DesignThe alignment of a road is shown on theplan view(平面图)andis a series of straight lines calledtangents([′tændʒənt]n.切线，正切，直线)connected by circular curves.

道路的线形以平面图形式给出，是由圆曲线连接的一系列称为切线的直线段所组成。

In modern practice it is common to interpose transition or spiralcurves between tangents and circular curves.

现在的做法通常是在切线和圆曲线之间插入缓和曲线和螺旋曲线。

第11页：设计要素的均衡

Alignment DesignFor balance in highway design all elements should, as far aseconomically feasible, be determined to provide safe, continuousat a speed likely under the general conditions for that highway orstreet.

为了保证道路设计的均衡，所有设计要素的确定，只要是经济上可行的，都应在公路或城市道路的一般条件下能够提供车辆安全、连续的行驶条件。

The least costly alignment is one that generally takes the formof the naturaltopography. ([tə′pɔɡrəfi]n.

地形，地貌，地势)最经济的线形设计一般是一条顺应自然地形的路线。

第12页：纵断面与竖曲线

Alignment DesignThe design of the vertical alignment therefore involves theselection of suitable grades for the tangent sections and thedesign of the vertical curves.

纵向线形设计因此也涉及了适应切线段的合适坡度和竖曲线设计。

The topography of the area through which the road traverseshas a significant impact on the design of the vertical alignment.

道路所通过地区的地形图对于纵向线形的设计具有非常重要的影响。

The curves are usually segments of circles, which have radiithat will provide for a smooth flow of traffic along the curve.

曲线通常为圆曲线，该曲线半径要求能够提供一条畅通的道路。

第13页：道路设计图纸内容

Alignment DesignThese plans show, for example, the dimensions of suchelements as roadway width, the final profile for the road, thelocation and type ofdrainage([dreinidʒ]n.排水，排水系统，下水道)facilities, and the quantities of work involved, includingearthwork and surfacing.

这些图纸显示了比如道路宽度等尺寸大小、道路最终的轮廓图、排水设施的位置和类型，工程涉及到的工程量，包括土方工程和路面工程。

第14页：公路养护内容

Highway MaintenanceHighway maintenance consists of the repair and upkeep ofsurfacing and shoulders, bridges and drainage facilities, signs,traffic control devices,guard rails(护栏，护轨), traffic striping onthe pavement, retaining walls, and side slopes.

公路维护包括路面、路肩、桥梁、排水设施、信号、交通控制设施、护栏、交通标线、挡土墙和边坡的维修和保养。

Because it is valuable to know why some highway designs givebetter performance and prove less costly to maintain than others,engineerssupervising(['sju:pəvaiz]vt.&vi.监管)maintenancecan offer valuable guidance to design engineers.

因为了解一些公路设计运行良好并且维护造价低的原因是很有必要的，所以维护监理工程师可以为设计工程师提供很有价值的指导。

第15页：Section B 路基与路面

Chapter 11 Highway EngineeringSection B Subgrades and Pravement

第16页：路面的主要功能

The purpose of apavement([′peivmənt]n.铺过的路面，硬路面)is providing a smooth surface over which vehicles may passunder all climatic conditions.

路面的主要作用就是在任何气候条件下提供车辆通行所需的平顺的表面。

In turn, the performance of the pavement is affected by thecharacteristics of thesubgrade([′sʌbgreid]n.

地基，路基).相应的路面性能会受到路基特性的影响。

第17页：路基的定义

Highway subgrade (orbasement soil[土路基，基土]) may bedefined as the supporting structure on which pavement and itsspecial under-courses rest.

公路路基（或土路基）被定义为路面和下面层的支撑结构。

In cut sections, the subgrade is the original soil lying below thespecial layers designated as base and subbase material.

在挖方断面上，路基是位于面层下部作为基础材料的原状土壤。

In fill section, the subgrade is constructed over the nativeground and consists of imported material from nearby roadwaycuts or fromborrow pits(取土坑，借土坑).

在填方断面上，路基修建在天然土层上和由附近挖方或外调土方所构成的土层上。

第18页：路基的横断面形式

The cross-sectional shape of the subgrade depends on the typeof surfacing, if any, which is to be used.

路基的横断面形状取决于使用中的路面类型，如果有路面的话。

On earth roads, the subgrade, which is also the surface course,is shaped to the standard road cross section.

在土路上，路基也是上面层，并且构成了标准的道路横断面。

If the trench method is used, the earth escalated to form atrench is pushed to the sides of the road to form retainingshoulders.

如果采用路槽法，那么要将做路槽所挖出的土推到路两边以便形成起支挡作用的路肩。

第19页：路基应具备的性质

Desirable properties which the subgrade should possessinclude strength, drainage, ease of compaction, permanency ofcompaction, and permanency of strength.

路基应该具有的性质包括强度、排水、便于压实、压实耐久性和强度耐久性。

The subgrade is usually the natural material located along thehorizontal alignment of the pavement and serves as thefoundation of the pavement structure.

路基一般都是位于路面平面线形附近的天然材料，其作用是作为路面结构的基础。

第20页：路基材料的选择处理

The subgrade may also consist of a layer of selected borrowmaterials, well compacted toprescribed([pri′skraibd]adj.规定的，法定的)specifications.

其组成也可以是一层经过选择并且充分压实达到规范规定的外调材料。

It may be necessary to treat the subgrade material to achievecertain strength properties required for the type of pavement beingconstructed.

对于路基材料必须进行必要的处理使其能够达到一定的强度特性来满足路面施工的要求。

第21页：路基土的试验研究

Since subgrades vary considerably, it is necessary to make athorough study of the soils in place and, from this, to determinethe design of the pavement.

因为路基土的差别很大，所以对现场土壤需要进行深入的研究以确定路面的设计。

Soil is a highly variable material, the interrelationship of soiltexture, density,moisture([′mɔistʃə]n.水分，水气，湿度，潮度)content, and strength are complex, and, in particular, behaviorunder repeated loads is difficult to evaluate.

土壤是一种高度可变的材料，土质间的相互影响、密度、含水量以及强度都很复杂，尤其是在反复荷载作用下的性能很难评估。

第22页：路基设计的技术程序

Because of the complexity of the problem, it is not possible toset down(规定，制定)rules which will be suitable for all cases.

因为问题的复杂性，所以很难制定一个统一的规则来适应所有情况。

Nevertheless, it is possible to formulate techniques andprocedures which will give satisfactory results if the principlesinvolved in design of the subgrade are readily understood by thedesign engineer.

然而，可能做到的就是制定相关的技术和程序来给出满意的解决方案，这样设计师就会很容易理解路基设计原理了。

第23页：路面结构的功能

A highway pavement is a structure consisting ofsuperimposed([′sju:pərim′pəuz]v.添（附）加，重叠)layers of selected andprocessed materials placed on a subgrade, whose primaryfunction is to support the applied traffic loads and distributeimposed wheel loads over a large area of the natural soil.

路面就是位于路基之上的由选择和处理过的材料叠合而成的结构，它的主要功能是支撑交通荷载并且将车轮荷载分布到下部大面积的天然土层之中。

第24页：车轮荷载与剪切失效

If vehicles were to travel on the natural soil itself, shear failureswould occur in the wheel path in most soils, andruts([rʌt]n.车辙，凹槽；vt.形成车辙)would form.

如果车轮直接行驶于天然土层上，那么在车轮痕迹的位置有可能发生剪切失效，随后车辙形成。

In addition to its load distribution function, the surface course ofa highway or airport pavement structure must provide a level, safetraveling surface.

除非所承担的荷载进行了扩散，道路或机场的路面结构才能提供安全的行驶表面。

第25页：柔性路面与刚性路面

The ultimate aim is to ensure that the transmitted stresses aresufficiently reduced that they will not exceed thesupportingcapacity(承载能力)of the subgrade.

最终目的是保证所传递的应力可以充分的降低，使之不超过路基的承载能力。

Highway pavements are divided into two main categories:flexible pavements(柔性路面)andrigid pavements(刚性路面),depending on how they distribute surface loads.

根据如何分布路表荷载，公路路面分为两大类：柔性路面和刚性路面。

第26页：两类路面的磨耗层

Thewearing surface([路面]磨耗层)of flexible pavements isusually constructed ofbituminous([bi′tju:minəs]adj.（含）沥青的)material such that they remain in contact with the underlyingmaterial even when minor irregularities occur.

柔性路面的磨耗层通常由沥青材料铺筑而成，这样即使出现小的缺陷，它也会和下卧层保持紧密联系。

The wearing surface of a rigid pavement, on the other hand, isusually constructed ofPortland cement(波特兰水泥，普通硅酸盐水泥)concrete such that it acts like a beam over any irregularitiesin the underlying supporting material.

另一方面，刚性路面的磨耗层通常用水泥混凝土铺筑，其作用与梁一样，支撑在不平整的下部材料上工作。

第27页：刚性与柔性路面的区别

The essential difference between the two types of pavement,flexible and rigid, is the manner in which they distribute the loadover the subgrade.

两种类型路面，柔性路面和刚性路面的本质区别是它们将荷载到路基的方式不同。

The rigid pavement, because of itsrigidity([ri′dʒiditi]n.刚度，坚硬，刚性，硬度)and high modulus of elasticity, tends todistribute the load over a relatively wide area of soil; thus, a majorportion of the structural capacity is supplied by theslab([slæb]n.板，板状物，厚板)itself.

由于刚性路面刚度大和弹性模量高，往往会把荷载分布到比较大面积的土壤中，这样结构承载力的主要承担部分就是板本身。

第28页：刚性路面的三种类型

For this reason, minor variations in subgrade strength have littleinfluence upon the structural capacity of the pavement.

正因为这个原因，即使路基强度出现微小的变化也不会影响路面承载能力。

Rigid highway pavement is divided into three general types:plain concrete pavement,simply reinforced concretepavement(普通加筋混凝土路面), andcontinuously reinforcedconcrete pavements(连续加筋混凝土路面).

刚性公路路面划分为三种类型：素混凝土路面，普通加筋混凝土路面和连续加筋混凝土路面。

第29页：刚性路面的使用寿命

Rigid highway pavements usually are constructed to carryheavy traffic loads, although they have been used for residentialand local roads.

尽管刚性路面道路已经应用于民用和地方道路，但是通常它可以承担重交通荷载。

Properly designed and constructed rigid pavements have longservice lives and usually are less expensive to maintain than theflexible pavements.

如果设计得当并且保证施工质量，刚性路面的使用寿命会很长，而且其维护费用比柔性路面要低。

第30页：柔性路面的组成

Theload-carrying capacity(承载能力，载重量)of flexiblepavements is brought about by the load-distributing characteristicsof thelayered system(层状体系).

柔性路面的承载能力是由层状系统的荷载分布特性提供的。

The components of a flexible pavement include the subgrade orprepared roadbed(填筑好的路基), the subbase, base course,and thesurface course(面层).

柔性路面的组成部分包括天然路基或填筑好的路基、底基层、基层和面层。

第31页：柔性路面性能评价

The performance of the pavement depends on the satisfactoryperformance of each component, which requires properevaluation of the properties of each component separately.

路面的性能取决于各组成部分的性质，这就要求对每个部分分别进行准确的评价。

Ideally, the pavement is built to a depth where stresses on anygiven layer will not cause undue rutting, shoving, and otherdifferential movements resulting in an uneven wearing surface.

最理想的情况是所修建的路面深度范围内，任何一个给定的层间都不会引起车辙、拥包和导致磨耗层不平整的变相差。

第32页：柔性路面的三个等级

Flexible pavements are further divided into three subgroups:high type, intermediate type, and low type.

柔性路面进一步可分为三个类型：高级、中级和低级。

High-type pavements(高级路面)have wearing surfaces thatadequately support the expected traffic load without visibledistress due tofatigue([fə′ti:ɡ]n.疲劳，劳累)and are notsusceptible([sə′septəbl]adj.能经受的，易受影响的，过敏的)toweather conditions.

高级路面的磨耗层能有效地承担预期的车辆荷载，而不会出现明显的疲劳破坏，并且不易受气候的影响。

第33页：中级与低级路面

Intermediate-type pavements have wearing surfaces that rangefromsurface treated(表面处治)to those with qualities just belowthat of high-type pavements.

中级路面的磨耗层无论是表面处理或是路面本身的质量都仅低于高级路面。

Low-type pavements are used mainly for low-cost roads andhave wearing surfaces that range from untreated toloose naturalmaterials(天然松散材料)to surface-treated earth.

低级路面主要用于低成本道路，它的磨耗层是表面未经处理的天然松散材料。