道桥专业英语.pptx

,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,道路与桥梁工程,专业英语,1/30,第一讲 绪论,一,.,专业英语是什么（,what,）？,二,.,为何要学习专业英语（,why,）？,三,.,怎么样学习专业英语（,how,）？,2/30,第一讲 绪论,一,.,专业英语是什么（,what,）？,1,、概念,专业英语：,English for special purpose,简称,ESP,。,专业：针对对应专业知识，专业术语，专业常识，所以应以专业知识理论为基础。,英语：国际语言，便于交流，包含学术交流、文件参阅、文章撰写等。,3/30,4/30,第一讲 绪论,一,.,专业英语是什么（,what,）？,2,、特点,2.1,语言特点,语言简练，表示明确，不重润饰,The shoulder width of urban and rural freeways is dependent upon the number of lanes of the facility.The right side shoulder for both urban and rural freeways shall be 10 feet.This width allows for emergency parking of vehicles on the right hand shoulder.The left side shoulder is dependent on the number of freeway lanes.,5/30,第一讲,一,.,专业英语是什么（,what,）？,2,、特点,2.1,语言特点,逻辑严谨，概念清楚，关系分明,Asphalt is called a bituminous material because it contains bitumen,a hydrocarbon material soluble in carbon disulfate(,一个易溶于二硫化碳烃类物质,),.The tar(,焦油）,obtained from the destructive distillation of soft coal also contains bitumen.Both petroleum asphalt and coal tar are referred to as bituminous materials.,6/30,第一讲 绪论,一,.,专业英语是什么（,what,）？,2,、特点,2.2,语法特点,非人称语气和客观态度，惯用,It,结构,It is important,though,to design freeways,urban and rural,that provide a consistent roadway for drivers.,7/30,第一讲 绪论,一,.,专业英语是什么（,what,）？,2,、特点,2.2,语法特点,多用被动结构,A freeway may be defined as a divided highway facility having two or more lanes for the exclusive use of traffic in each direction and full control of access and egress.,高速公路可定义为每个方向含有两条或两条以上汽车专用车道，而且进出口完全控制被分隔公路设施。,8/30,第一讲 绪论,一,.,专业英语是什么（,what,）？,2,、特点,2.2,语法特点,多用动词非谓语结构,In general,the design speed of freeways should be similar to the desired running speed during off peak hours,keeping in mind a reasonable and prudent speed.,9/30,第一讲 绪论,一,.,专业英语是什么（,what,）？,2,、特点,2.2,语法特点,祈使语句和公式化表示方式,在理论分析和公式推导中常采取,Assume that,，,Suppose that,，,Let,等祈使语气表示方式。,So,next let us look at how to use SYNCHRO to do signal timing and simulation work.,所以，接下来让我们看看怎样使用,SYNCHRO,来进行信号配时和交通仿真工作。,10/30,第一讲 绪论,一,.,专业英语是什么（,what,）？,2,、特点,2.2,语法特点,条件句较多,条件句多用于条件叙述、理论分析和公式推导中，最惯用是,If,语句。,The huge investment in the highway infrastructure will be erased quickly if proper maintenance and rehabilitation procedures are enforced and funded.,若合理养护和修护计划得以资助并实施，就可快速取消用于公路基础建设巨大投资。,11/30,第一讲 绪论,一,.,专业英语是什么（,what,）？,2,、特点,2.2,语法特点,多用长句,One of the effects of oxidation is that the binder loses flexibility and therefore becomes harder and more susceptible to the abrasive effects of traffic;an oxidized binder is thus likely to wear away in preference to particles of coarse aggregate set in the surface,allowing the chippings to protrude from the surface and improve the skidding resistance.,12/30,第一讲 绪论,一,.,专业英语是什么（,what,）？,2,、特点,2.2,语法特点,省略句较多,为了简练，有时省略掉句子中一些成份，如状语从句中主语和谓语、定语从句中关联词,which,或,that,从句中助动词等。,If not well managed,the procedure for construction may be more expensive.,假如管理不善，这一施工方法还可能更费钱。,常见省略（状语从句中主语和谓语）句型有：,As already discussed,前已讨论,If possible,假如可能话,As described above,如前所述,If so,倘若如此,As explained before,前已解释,When necessary,必要时,As indicated in Fig.1,如图,1,所表示,When needed,需要时,As previously mentioned,前已述及,Where feasible,在实际可行场所,If necessary,假如必要话,Where possible,在可能情况下,13/30,第一讲 绪论,一,.,专业英语是什么（,what,）？,2,、特点,2.2,语法特点,大量使用名词化结构,名词化特点主要是指在专业文件中广泛使用能表示动作和状态名词，或是起名词作用非限定动词。,In the initial stages of road design it is usual for several alternative route proposals to be considered but only outline details of road center lines and estimates of speeds and flows are available.,在道路设计初始阶段，通常有各种备选路线方案需要考虑，但这时只有道路中线概要数据和车速及流量预测值。,14/30,第一讲 绪论,一,.,专业英语是什么（,what,）？,2,、特点,2.3,词汇特点,专业词汇,2.4,结构特点,每一自然段落中，总有,一个语句概括出该段落重点,。这个语句或在段落之首，或在段落之尾，较少出现在段落中间。若干个自然段会形成一个逻辑（或结构）段落，用以从不一样角度来,讲解某一层面关键内容,。全篇则由若干个逻辑段落组成，从不一样层面来阐述文章标题所标明中心思想。实际上，专业文件中通常采取标题、子标题、编号等形式，就是对文章结构逻辑划分,15/30,Highway engineering is an engineering discipline branching from civil engineering which involves the design,construction and maintenance of highway systems.,Highway engineering became prominent towards the latter half of the 20th Century after World War 2.Standards of highway engineering are continuously being improved.Highway engineers must take into account future traffic flows,design of highway intersections/interchanges,geometric alignment and design,highway pavement materials and design,structural design of pavement thickness,and pavement maintenance.Most developed nations have extensive highway networks.,16/30,The most appropriate location,alignment,and shape of a highway are selected during the design stage.Highway design involves the consideration of three major factors(human,vehicular,and roadway)and how these factors interact to provide a safe highway.,Human factors include reaction time for braking and steering,visual acuity for traffic signs and signals,and car-following behavior.,17/30,Vehicle considerations include vehicle size and dynamics that are essential for determining lane width and maximum slopes,and for the selection of design vehicles.Highway engineers design road geometry to ensure stability of vehicles when negotiating curves and grades and to provide adequate sight distances for undertaking passing maneuvers along curves on two-lane,two-way roads.,vehicle dynamics,汽车动力,lane width,车道宽度,maximum slopes,最大纵坡度,design vehicles,设计车辆,design vehicles,视距,two-lane,two-way roads,双向双车道,道路,18/30,Geometric Design,Highway and transportation engineers must meet many safety,service,and performance standards when designing highways for certain site topography.,Highway geometric design primarily refers to the visible elements of the highways.Highway engineers who design the geometry of highways must also consider environmental and social effects of the design on the surrounding infrastructure,（基础设施）,.,19/30,Geometric Design,There are certain considerations that must be properly addressed in the design process to successfully fit a highway to a sites topography and maintain its safety.Some of these design considerations include Design speed,Design traffic volume,Number of lanes,Level of Service(LOS),Sight Distance,super-elevation,and grades,Cross section,Lane width,Horizontal and vertical clearance.The operational performance of a highway can be seen through drivers reactions to the design considerations and their interaction.,Level of Service(LOS),服务水平,Sight Distance-,视距,super-elevation-,超高,Grade-,纵坡度,cross section-,横断面,lane width-,车道宽,20/30,Materials,The materials used for roadway construction have progressed with time,dating back to the early days of the Roman Empire.,Advancements in methods with which these materials are characterized and applied to pavement structural design has accompanied this advancement in materials.There are two major types of pavement surfaces-Portland cement concrete(PCC)and hot-mix asphalt(HMA).,Portland cement concrete(PCC)-,普通硅酸盐水泥,hot-mix asphalt(HMA)-,热拌沥青混合料,21/30,Flexible Pavement Design,A flexible,or asphalt,pavement typically consists of three or four layers.,For a four layer flexible pavement,there is a surface course,base course,and subbase course constructed over a compacted,natural soil subgrade.When building a three layer flexible pavement,the subbase layer is not used and the base course is placed directly on the natural subgrade.,Flexible Pavement,柔性路面,surface course-,面层,Layers-,结构层,base course-,基层,subbase course-,底基层,soil subgrade-,土基,22/30,A flexible pavements surface layer is constructed of hot-mix asphalt(HMA).,Unstabilized aggregates are typically used for the base course;however,the base course could also be stabilized with asphalt,Portland cement,or another stabilizing agent.The subbase is generally constructed from local aggregate material,while the top of the subgrade is often stabilized with cement or lime.,23/30,With a flexible pavement,the highest stress occurs at the surface and the stress decreases as the depth of the pavement increases.Therefore,the highest quality material needs to be used for the surface,while lower quality materials can be used as the depth of the pavement increases.,Stress-,应力；,24/30,The term flexible is used because of the asphalts ability to bend and deform slightly,then return to its original position as each,traffic load,is applied and removed.It is possible for these small deformations to become permanent,which can lead to,rutting,in the wheel path over an extended time.The,service life,of a flexible pavement is typically designed in the range of 15 to 20 years.,traffic load,车辆荷载,Rutting,车辙,service life,使用寿命,25/30,Rigid Pavement,Rigid pavements are generally used in constructing airports and major highways,such as those in the interstate highway system.Like flexible pavements,rigid highway pavements are designed as all-weather,long-lasting structures to serve modern day high-speed traffic.,Rigid pavements-,刚性路面；,all-weather-,全天候；,long-lasting-,持久；,26/30,Rigid Pavement,Offering high quality riding surfaces for safe vehicular travel,they function as structural layers to distribute vehicular wheel loads in such a manner that the induced stresses transmitted to the subgrade soil are of acceptable magnitudes.,27/30,Portland cement concrete(PCC)is the most common material used in the construction of rigid pavement slabs.The reason for its popularity is due to its availability and the economy.Rigid pavements must be designed to endure frequently repeated traffic loadings.The typical designed service life of a rigid pavement is between 30 and 40 years,lasting about twice as long as a flexible pavement.,28/30,二,.,为何要学习专业英语（,why,）？,1,、,Reading,2,、,Translation and Interpretation,（笔译和口译）,3,、,Writing,29/30,三,.,怎么样学习专业英语（,how,）？,1,、掌握专业词汇；,2,、大量阅读专业学科论文；,3,、学会进行英文论文检索,(,第,3,章）；,4,、尝试着翻译（第四章）和写作（第五章）。,30/30,