道桥专业英语一ppt课件.ppt

道路与桥梁工程专业英语 第一讲绪论 一 专业英语是什么 what 二 为什么要学习专业英语 why 三 怎么样学习专业英语 how 第一讲绪论 一 专业英语是什么 what 1 概念专业英语 Englishforspecialpurpose 简称ESP 专业 针对相应专业知识 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 包括学术交流 文献参阅 文章撰写等 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 表达明确 不重润饰Theshoulderwidthofurbanandruralfreewaysisdependentuponthenumberoflanesofthefacility Therightsideshoulderforbothurbanandruralfreewaysshallbe10feet Thiswidthallowsforemergencyparkingofvehiclesontherighthandshoulder Theleftsideshoulderisdependentonthenumberoffreewaylanes 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 概念清晰 关系分明Asphaltiscalledabituminousmaterialbecauseitcontainsbitumen ahydrocarbonmaterialsolubleincarbondisulfate 一个易溶于二硫化碳烃类物质 Thetar 焦油 obtainedfromthedestructivedistillationofsoftcoalalsocontainsbitumen Bothpetroleumasphaltandcoaltararereferredtoasbituminousmaterials 第一讲绪论 一 专业英语是什么 what 2 特点2 2语法特点非人称的语气和客观的态度 常用It 结构Itisimportant though todesignfreeways urbanandrural thatprovideaconsistentroadwayfordrivers 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Afreewaymaybedefinedasadividedhighwayfacilityhavingtwoormorelanesfortheexclusiveuseoftrafficineachdirectionandfullcontrolofaccessandegress 高速公路可定义为每个方向具有两条或两条以上汽车专用车道 并且进出口完全控制的被分隔的公路设施 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Ingeneral thedesignspeedoffreewaysshouldbesimilartothedesiredrunningspeedduringoffpeakhours keepinginmindareasonableandprudentspeed 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达方式在理论分析和公式推导中常采用Assumethat Supposethat Let 等祈使语气表达方式 So nextletuslookathowtouseSYNCHROtodosignaltimingandsimulationwork 因此 接下来让我们看看如何使用SYNCHRO来进行信号配时和交通仿真工作 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论述 理论分析和公式推导中 最常用的是If 语句 Thehugeinvestmentinthehighwayinfrastructurewillbeerasedquicklyifpropermaintenanceandrehabilitationproceduresareenforcedandfunded 若合理的养护和修护计划得以资助并实施 就可迅速取消用于公路基础建设的巨大投资 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Oneoftheeffectsofoxidationisthatthebinderlosesflexibilityandthereforebecomesharderandmoresusceptibletotheabrasiveeffectsoftraffic anoxidizedbinderisthuslikelytowearawayinpreferencetoparticlesofcoarseaggregatesetinthesurface allowingthechippingstoprotrudefromthesurfaceandimprovetheskiddingresistance 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洁 有时省略掉句子中的一些成分 如状语从句中的主语和谓语 定语从句中的关联词which或that 从句中的助动词等 Ifnotwellmanaged theprocedureforconstructionmaybemoreexpensive 如果管理不善 这一施工方法还可能更费钱 常见的省略 状语从句中的主语和谓语的 句型有 Asalreadydiscussed前已讨论Ifpossible如果可能的话Asdescribedabove如前所述Ifso倘若如此Asexplainedbefore前已解释Whennecessary必要时AsindicatedinFig 1如图1所示Whenneeded需要时Aspreviouslymentioned前已述及Wherefeasible在实际可行的场合Ifnecessary如果必要的话Wherepossible在可能的情况下 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献中广泛使用能表示动作和状态的名词 或是起名词作用的非限定动词 Intheinitialstagesofroaddesignitisusualforseveralalternativerouteproposalstobeconsideredbutonlyoutlinedetailsofroadcenterlinesandestimatesofspeedsandflowsareavailable 在道路设计的初始阶段 通常有多种备选的路线方案需要考虑 但这时只有道路中线的概要数据和车速及流量的预测值 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的重点 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 用以从不同角度来解说某一层面的核心内容 全篇则由若干个逻辑段落组成 从不同层面来阐述文章标题所标明的中心思想 实际上 专业文献中通常采用的标题 子标题 编号等形式 就是对文章结构的逻辑划分 Highwayengineeringisanengineeringdisciplinebranchingfromcivilengineeringwhichinvolvesthedesign constructionandmaintenanceofhighwaysystems Highwayengineeringbecameprominenttowardsthelatterhalfofthe20thCenturyafterWorldWar2 Standardsofhighwayengineeringarecontinuouslybeingimproved Highwayengineersmusttakeintoaccountfuturetrafficflows designofhighwayintersections interchanges geometricalignmentanddesign highwaypavementmaterialsanddesign structuraldesignofpavementthickness andpavementmaintenance Mostdevelopednationshaveextensivehighwaynetworks Themostappropriatelocation alignment andshapeofahighwayareselectedduringthedesignstage Highwaydesigninvolvestheconsiderationofthreemajorfactors human vehicular androadway andhowthesefactorsinteracttoprovideasafehighway Humanfactorsincludereactiontimeforbrakingandsteering visualacuityfortrafficsignsandsignals andcar followingbehavior Vehicleconsiderationsincludevehiclesizeanddynamicsthatareessentialfordetermininglanewidthandmaximumslopes andfortheselectionofdesignvehicles Highwayengineersdesignroadgeometrytoensurestabilityofvehicleswhennegotiatingcurvesandgradesandtoprovideadequatesightdistancesforundertakingpassingmaneuversalongcurvesontwo lane two wayroads vehicledynamics 汽车的动力lanewidth 车道宽度maximumslopes 最大纵坡度designvehicles 设计车辆designvehicles 视距two lane two wayroads 双向双车道道路 GeometricDesignHighwayandtransportationengineersmustmeetmanysafety service andperformancestandardswhendesigninghighwaysforcertainsitetopography Highwaygeometricdesignprimarilyreferstothevisibleelementsofthehighways Highwayengineerswhodesignthegeometryofhighwaysmustalsoconsiderenvironmentalandsocialeffectsofthedesignonthesurroundinginfrastructure 基础设施 GeometricDesignTherearecertainconsiderationsthatmustbeproperlyaddressedinthedesignprocesstosuccessfullyfitahighwaytoasite stopographyandmaintainitssafety SomeofthesedesignconsiderationsincludeDesignspeed Designtrafficvolume Numberoflanes LevelofService LOS SightDistance super elevation andgrades Crosssection Lanewidth Horizontalandverticalclearance Theoperationalperformanceofahighwaycanbeseenthroughdrivers reactionstothedesignconsiderationsandtheirinteraction LevelofService LOS 服务水平SightDistance 视距super elevation 超高Grade 纵坡度crosssection 横断面lanewidth 车道宽 MaterialsThematerialsusedforroadwayconstructionhaveprogressedwithtime datingbacktotheearlydaysoftheRomanEmpire Advancementsinmethodswithwhichthesematerialsarecharacterizedandappliedtopavementstructuraldesignhasaccompaniedthisadvancementinmaterials Therearetwomajortypesofpavementsurfaces Portlandcementconcrete PCC andhot mixasphalt HMA Portlandcementconcrete PCC 普通硅酸盐水泥hot mixasphalt HMA 热拌沥青混合料 FlexiblePavementDesignAflexible orasphalt pavementtypicallyconsistsofthreeorfourlayers Forafourlayerflexiblepavement thereisasurfacecourse basecourse andsubbasecourseconstructedoveracompacted naturalsoilsubgrade Whenbuildingathreelayerflexiblepavement thesubbaselayerisnotusedandthebasecourseisplaceddirectlyonthenaturalsubgrade FlexiblePavement 柔性路面surfacecourse 面层Layers 结构层basecourse 基层subbasecourse 底基层soilsubgrade 土基 Aflexiblepavement ssurfacelayerisconstructedofhot mixasphalt HMA Unstabilizedaggregatesaretypicallyusedforthebasecourse however thebasecoursecouldalsobestabilizedwithasphalt Portlandcement oranotherstabilizingagent Thesubbaseisgenerallyconstructedfromlocalaggregatematerial whilethetopofthesubgradeisoftenstabilizedwithcementorlime Withaflexiblepavement thehigheststressoccursatthesurfaceandthestressdecreasesasthedepthofthepavementincreases Therefore thehighestqualitymaterialneedstobeusedforthesurface whilelowerqualitymaterialscanbeusedasthedepthofthepavementincreases Stress 应力 Theterm flexible isusedbecauseoftheasphaltsabilitytobendanddeformslightly thenreturntoitsoriginalpositionaseachtrafficloadisappliedandremoved Itispossibleforthesesmalldeformationstobecomepermanent whichcanleadtoruttinginthewheelpathoveranextendedtime Theservicelifeofaflexiblepavementistypicallydesignedintherangeof15to20years trafficload 车辆荷载Rutting 车辙servicelife 使用寿命 RigidPavement Rigidpavementsaregenerallyusedinconstructingairportsandmajorhighways suchasthoseintheinterstatehighwaysystem Likeflexiblepavements rigidhighwaypavementsaredesignedasall weather long lastingstructurestoservemo