《专业英语翻译》-Part II Introduction of Civil Engineering

Unit2-1CivilEngineeringCivilengineeringisdefinedasageneraldisciplineofscienceandtechnologytobuildallengineeringconstructionandfacilities.Itincludesallconstructionobjects，i.e.buildings，transportationfacilities，infrastructures，etc.，andmaterialsaswellasprofessionrequiredduringtheprocessesofdesign，construction，andmaintenance.下一页返回Unit2-1CivilEngineeringCivilengineeringisthebroadestdisciplinesinengineeringfields，extendingacrossmanytechnicalspecialtiesthatarenotindependentbutinteractwitheachother.Overthepastcoupleofdecades，thebroadfieldofcivilengineeringhasbeenspecializedinanumberofareas.Majorspecialtieswithincivilengineeringare:Structuralengineering;WaterresourcesengineeringEnvironmentalengineering;上一页下一页返回Unit2-1CivilEngineeringTransportationengineering;Surveyingengineering;Geotechnicalengineering.StructuralEngineeringStructuralengineeringdealswiththedesignandconstructionofalltypesofstructuresincludingbuildingsandbridges(ShowninFig.1andFig.2).Thejobofstructuralengineersistocreatethenewdesignsortoevaluateandimprovetheloadresistancecapabilitiesofexistingstructureswhichmayhavebeendamagedduringanearthquake.上一页下一页返回Unit2-1CivilEngineeringThestructuralengineermustbeknowledgeableaboutthebehaviorofdeformablebodies，aboutthesources，magnitudesandprobabilityofoccurrenceofappliedloads，aboutmaterialproperties，designphilosophieandgovernmentaldesigncodes，andaboutcomputerprogrammingandusage.上一页下一页返回Unit2-1CivilEngineeringWaterResourcesEngineeringWaterresourcesengineeringcoverstheplanning，management，designandoperationofwatersupplyanddistributionsystems，floodcontrolandfloodhazardmapping，hydrologicandhydraulicaspectsofenvironmentalproblems.SanXiaDamisafamouswaterresourcesengineeringinChina.ShowninFig.3.上一页下一页返回Unit2-1CivilEngineeringWaterresourcesengineeringusuallydealswiththeapplicationoffluidmechanicsprinciplestowaterflowproblems，butmayalsoincludefluidsrangingfrombloodtomagma.Someproblemsencounteredinwaterresourcesengineeringinclude:floods，sedimenttransport,watersupply，waveforces，hydro-machinery，andtheprotectionorrestorationofsurfaceandgroundwaterresources.Engineersinthehydraulics/hydrologyareamayspendtheirtimewithappliedmathematics，laboratoryexperimentation，orfieldconstructionandtesting.上一页下一页返回Unit2-1CivilEngineeringEnvironmentalEngineeringEnvironmentalengineeringisconcernedwithairpollution，waterpollution，solidwastemanagement，radiologicalhazardcontrol，pesticidehazardcontrolandwatersupply.Environmentalengineersdesignsystemssuchas，watertreatment/distributionsystemsandwastewatertreatmentfacilitiestoprovidesafedrinkingwaterandtopreventandcontrolpollutioninwater,air,land，andgroundwater.ShowninFig.4.上一页下一页返回Unit2-1CivilEngineeringTransportationEngineeringTransportationengineeringisconcernedwiththemovementofpeopleandgoodsbymeansofasystemoffixedfacilitiesandacontrolsystemthatpermitsmovementingeographicalspaceinanefficientandorderlymanner.Transportationengineersfocusontheplanning，designSystemsConstructionandmanagementoftransportationsystems.Theseconsistofthefacilities，vehicles，controlmechanisms，andpoliciesthatarecombinedtopermittheefficientconveyanceofpeopleandgoods.ShowninFig.5-Fig.7.上一页下一页返回Unit2-1CivilEngineeringSurveyingEngineeringSurveyingengineeringisinvolvedintheprecisemeasurementoftheearth'ssurfacetoobtainreliableinformationforlocatinganddesigningengineeringprojects.Evenbeforeadesigniscompleted，andasconstructionprogresses，teamsofsurveyingandmappingengineersareatworkModernsurveyingandmappingengineeruseelectronicinstrumentsandevensatellitestomeasurethedimensionsoftheproject.ShowninFig.8and9.上一页下一页返回Unit2-1CivilEngineeringGeotechnicalEngineeringGeotechnicalengineeringisadisciplineofcivilengineeringthatdealswithsoil，rockandundergroundwater,andtheirrelationtodesign，constructionandoperationofengineeringprojects.Geotechnicalengineersanalyzethepropertiesofsoilandrockthatsupportandaffectthebehaviorofstructure，pavementsandundergroundfacilities上一页下一页返回Unit2-1CivilEngineeringTheyevaluatethepotentialsettlementsofbuildings，thestabilityofslopesAndfills，theseepageofgroundwaterandtheeffectsofearthquakes.Theytakepartinthedesignandconstructionofearthstructures(dams，leveesEtc.)foundationsofbuildingsandstructuressuchasoffshoreplatforms，tunnels，anddams，anddevelopingexcavationtechniquesandconstructionmethodsfortunnelsandotherworks.上一页下一页返回NewWordsandExpressionsdisciplinen.训练;纪律;专业;学科训练:惩罚facilityn.容易，灵巧，设施;设备装备specialize v.(使)特殊化;专门研究，专门从事(in);特加指明，列举，逐条详述specialtyn n.特性，性质;专门研究;专业;专长;特产;特点;细节;特别事项surveyn n.纵览;视察;测量;俯瞰;调查geotechnical adj.地质的;土工的;岩土的;土力的evaluate vt.对……估价.对……作评价上一页下一页返回NewWordsandExpressionsmagnitude n.大小长(度);尺寸，幅〔度」;巨大;重要性property n.财产;所有物(不可数);地产，房地产;财产权distribution n.分配，分发;配给;配给物;分配装置;配给方法;mapping n.绘图，测绘;测图;定位，作图;〔数〕映象，映射hydrology n.水文学，水文地理学magma n.稠液:乳浆剂:岩浆:浮悬液上一页下一页返回NewWordsandExpressionsradiological adj.放射线学的;放射线的;放射性的;辐射的dimension n.尺寸(长，宽，高)，尺度，线度underground n.地下:地铁:地道:秘密活动adj.地下的;秘密的adj.在地下:秘密地pavement n.路面;人行道;铺面路;铺路材料settlement n.安顿;解决，处理;结算;殖民，殖民地;沉降seepage n.渗出，渗出量;渗出现象;渗滤;渗漏上一页下一页返回NewWordsandExpressionslevee n.(国王或贵族起床后的)早朝，接见;大堤excavation n.开凿;开挖;挖掘;穴，洞sedimenttransport 沉积物运移:泥沙流移:输砂:沉积物运输focuson 集中(在)上一页下一页返回Unit2-1CivilEngineeringfinancial adj.财政的，金融的outcome n.结果;成果;后果;结局analysis n.分解，分析;梗概，要略纲领;〔数〕解析，解析学，分析学alternative n.取舍，抉择，可供选择的事物credit n.信赖:荣誉:赞扬:贷款:信用证implementation n.执行.履行:落实investor n.投资者.投资方creditor n.债权人;贷方上一页下一页返回Unit2-1CivilEngineeringintangible adj.触摸不到的;无形的;不可捉摸的;难以确定的toll n.通行费，代价，钟声vt.征收.敲钟.鸣钟vi.征税.鸣钟deterrence n.制止:威慑:阻止aggregate vt.结合;集结;(使)聚集;共计上一页下一页返回Unit2-1CivilEngineeringExercises1.Fillintheblankswithsuitablewordsorexpressionsfromthelistgivenbelow，changingtheformwhennecessary.1._____engineeringdealswiththedesignandconstructionofalltypesofstructures.2.Thebroadestdisciplinesinengineeringfieldsis_____3.Evenbeforeadesigniscompleted，teamsof_____engineersareatwork.4.________engineersanalyzethepropertiesofsoilandrockthatsupportandaffectthebehaviorofstructure.上一页下一页返回Unit2-1CivilEngineering5.______engineeringisconcernedwithairpollution，waterpollution，solidwastemanagement，radiologicalhazardcontrol，pesticidehazardcontrolandwatersupply.6.Themovementofpeopleandgoodsarestudiedby_____engineering.7.______engineeringdealswithfloodcontrolandfloodhazardmapping，hydrologicandhydraulicaspectsofenvironmentalproblems.上一页下一页返回Unit2-1CivilEngineering11.WriteTinfrontofastatementifitistrueandwriteFifitisfalseaccordingtothetext.1.Structuralengineeringisthebroadestdisciplinesinengineeringfields.2.Surveyengineerstakepartinthedesignandconstructionofearthstructuresandfoundationsofbuildings.3.Transportationpoliciescanmaketheconveyanceofpeopleandgoodsmoreefficient.4.Environmentalengineeringincludesallconstructionobjects，i.e.buildings，transportationfacilities，infrastructures，etc.上一页下一页返回Unit2-1CivilEngineeringIII.TranslatethefollowingsentencesintoChinese.1.Structuralengineeringincludesallstructuresbuiltaccordingtoscientificprinciples，fromirrigationanddrainagesystemstorocket-launchingfacilities.2.Civilengineeringisthebroadestdisciplinesinengineeringfields，extendingacrossmanytechnicalspecialtiesthatarenotindependentbutinteractwitheachother.上一页返回Unit2-2CivilEngineeringMaterialsCivilengineeringmaterialscanbenaturalandmanmade.Theycontainrock,metals，timber,concrete，bitumen，soil，polymers，bricksandblocks，etc.Besidesthesetraditionalmaterials，newtypesofconstructionalmaterialsarealsoinvestigatedanddevelopedandwillbeappliedgradually.NowgreencivilengineeringmaterialsandTheeveneco-materialsforcivilengineeringarerecommendedbasedonconsiderationofsustainabledevelopment.下一页返回Unit2-2CivilEngineeringMaterialsThishasthebenefitsofreducingenergy，savingresourcesandprotectingtheenvironment，doingminimumharmtohumanhealth.TimberTimberisknownasoneoftheoldestcivilengineeringmaterials(Fig.1).Inadditiontoitsusefulnessasastructuralmaterial，timberhasalsofulfilledaroleintemporarystructures.Althoughtimberisakindofsustainableresource，theconsumptionspeedofforestsmustbesloweddownbecauseoftherelativeslownessoftreegrowth.上一页下一页返回Unit2-2CivilEngineeringMaterialsStrengthoftimberisaffectedbyfactorssuchasdensity，moisturecontentandgrainstructureaswellasbyvariousdefects.Densityisalmostcertainlyanindicationofstrength:themoredensethetimberhas，thestrongeritis.Thereisoptimummoisturecontentandanexcessivelydried-outtimbermayhavealowerstrength.Grainstructureandcontinuityareofsignificanceinastrengthcontextandanydisruptionduetogrowthdefectsorseasoningdefectswillinduceareductioninstrength.上一页下一页返回Unit2-2CivilEngineeringMaterialsMetalsMetalsconsistofferrousmetalsandnonferrousmetals.Theferrousmetalsmeanironandalloysmademainlyfromiron，whilethenonferrousmetalsincludealltheothermetalsandtheiralloys.Thepropertiesofmetalswhichmakethemuniqueamongconstructionalmaterialsarehightensilestrength，theabilitytobeformedintoplate，sectionsandwire，andtheweldability.上一页下一页返回Unit2-2CivilEngineeringMaterialsOtherpropertiesofmetalsareelectricalconductivity，highthermalconductivityandmetallicluster，whichareofimportanceinsomecircumstances.Perhapsthegreatestdisadvantageofthecommonmetals，andsteelsinparticular,istoprotectthemfromcorrosionmoistconditionsandatmosphere.上一页下一页返回Unit2-2CivilEngineeringMaterialsConcreteConcreteisaman-madecompositethemajorconstituentofwhichisnaturalaggregate(suchasgravelandsand)andbindingmedium(suchascementpaste，bitumenandpolymers).Thebindingmediumisusedtobindtheaggregateparticlestogethertoformahardcompositematerial.(Fig.4)上一页下一页返回Unit2-2CivilEngineeringMaterialsNormalconcretehasacomparativelylowtensilestrengthandforstructuralapplicationsitisnormalpracticeeithertoincorporatesteelbarstoresistanytensileforces(steelreinforcedconcrete)ortoapplycompressiveforcestotheconcretetocounteractthesetensileforces(prestressedconcreteorpos一stressedconcrete).ShowninFig.5.Constituentsinconcreteinclude:(1)Cement;(2)Aggregate;(3)Water;(4)Chemicaladmixtures;(5)Mineraladmixtures.上一页下一页返回Unit2-2CivilEngineeringMaterialsBituminousMaterialsBitumenisobtainedbythefractionaldistillationofpetroleum(crudeoil)Bituminousmaterialshavethefollowingpropertiesandadvantages:(1)relativecheapnessandavailabilityinlargequantities(2)durability;(3)goodadhesive;(4)theeasewithwhichtheycanbehandledatelevatedtemperatures,butquicklybecomestiffandresistanttodeformationatnormaltemperatures.上一页下一页返回Unit2-2CivilEngineeringMaterialsEarliestknownusesofbitumenrelatetohydraulicusesaswaterproofmaterials.Itisalsousedasgoodmaterialofchemical一attackresistance.Nowadaysthemainuseofbitumenisinroadsurfaces，namedbitumenconcreteroad.

上一页下一页返回NewWordsandExpressionsmanmade adj.人造的，人工的timber n.木材.木料vt.用木材建造bitumen adj.沥青moisture n.湿气，水分，潮湿;(空气中的)水蒸气grain n.谷粒:颗粒:谷类:纹理:本质optimum n.最优化:最优值ferrous adj.铁的，含铁的，亚铁的，二价铁的;ferrousmetal 黑色铁类一金属nonferrous adj.非铁的，不含铁的nonferrousmetals 有色(非铁)金属gravel n.砂砾，碎石;(医)肾结石，膀耽结石上一页下一页返回NewWordsandExpressionsincorporate adj.合并的，组成公司的，一体化的bitumious adj.沥青的，含沥青的adhesive adj.拈着的，涂有拈性物质的waterproof n.防水材料tensilestrength抗拉强度，拉伸强度tensileforce拉力compressiveforce压力reinforcedconcrete钢筋混凝土prestressedconcrete预应力混凝土pos一stressedconcrete后张法预应力混凝土crudeoil原油上一页下一页返回ExercisesI.Underlinethechoicesthatmakeeachstatementcorrectaccordingtothetext.1.Greencivilengineeringmaterialshave____harmtohumanhealth.A.mediumB.maximumC.minimumD.great2._____isknownasoneoftheoldestcivilengineeringmaterials.A.MetalB.TimberC.ConcreteD.Bitumen3.Atnormaltemperatures，bitumenquicklybecome____andresistanttodeformation.A.softB.warmC.stiffD.slight上一页下一页返回Exercises4.Normalconcretehasacomparatively______tensilestrength.A.highB.lowC.greatD.medium5.Thepropertiesofmetalswhichmakethemuniqueamongconstructionalmaterialsare____tensilestrength.A.highB.maximumC.minimumD.low上一页下一页返回ExercisesII.TranslatethefollowingsentencesintoChinese.1.Asweallknown，civilengineeringmaterialscanbenaturalandmanmade.2.Aggregateinconcretecanbeclassifiedascoarseaggregateandfineaggregateaccordingtoitsdiameter.3.Wheninservice，metalfrequentlyhavetoresistnotonlyhightensileorcompressivestressandcorrosion，butalsoconditionsofshockloadingandlowtemperatures.上一页下一页返回Exercises4.Grainstructureandcontinuityareofsignificanceinastrengthcontextandanydisruptionduetogrowthdefectsorseasoningdefectswillinduceareductioninstrength.5.Bituminousconcretemaybedensegraded，opengraded，gapgradedorintermediatebetweenthesetypes.Itmaybehotmixed-hotlaid，warmmixed-coldlaid，orcoldmixed-coldlaid.上一页下一页返回ExercisesIII.TranslatethefollowingsentencesintoEnglish.1.木材是最早被应用的土木工程材料之一。2.金属材料具有高抗拉强度，可以形成板材、型材和线材，并具有可焊性。3.沥青材料相对廉价和可大量应用，广泛应用于公路建设领域。上一页返回Unit2-3ConcreteCrackingReinforcedconcreteisacompositematerialwhereload-bearinganddeformationpropertiesaredeterminedbythebehaviorbetweentheelements一steelandconcrete一aswellastheindividualconstituentsoftheseelements，particularlythoseoftheconcrete.Concrete，atallages，hasalowtensilestrengthcomparedtothecompressivestrength.Underload，thetensilestrainbuildsinthetensilezone.Thistensilestrainistakenupbythereinforcementbutitisinevitablethatregularbutcontrolledcrackingwilloccur.下一页返回Unit2-3ConcreteCrackingThisisaccountedforaspartofthestructuraldesignprocess，wherethecrackwidthsarelimitedbyanappropriateareaofreinforcementsuitabletotheworkingenvironment.Tensilestrainandthepossibilityofcracking(flexure，shear,torsion，anchoragefailureetc.)donotonlyoccurduetostructuralloading.上一页下一页返回Unit2-3ConcreteCrackingMicro-crackswilldevelopintheconcreteattheinterfacesbetweenthesteelandcementpasteandaggregate，althoughonlyvisiblethroughamicroscope，duetointernalshrinkageetc.Thistypeofcrackingisnotcoveredhere.Crackscandevelopattheunformedsurfaceofimmatureconcreteduetoarapidreductionofvolumeatthesurface(plasticshrinkage).Ifaconcretebleedsexcessively，thedenserparticlestendtosettleoverembeddedmaterials，e.g.thereinforcement，causingthenearsurfacetotear(plasticsettlement).上一页下一页返回Unit2-3ConcreteCrackingInthesecasesthereinforcementdoesnotgenerallytakeupanytensilestrain，althoughmayaffectthecrackpatterndeveloped.Crackscanalsobeassociatedwithtemperaturecycles，eitherfromthehydratingconcreteatearlyagesorsolargain(thermal)，whererestraintagainstmovementpreventsexpansionorcontractionsothattensilestrainisinduced_Herethereinforcementaccommodatesthetensileforcesandinfluencesthecrackpattern.Otherformsofcracksfromchemicalactionsalsooccur.上一页下一页返回Unit2-3ConcreteCrackingThepresenceofcrackscaninfluencethebehavioranddurabilityofaconcretemember.Theycanreducetheshearcapacityofasectionorprovideapathbywhichmoisture，oxygen，carbondioxide，chloridesetc.canpenetrateintotheconcretesurroundingthereinforcementwhichintimemayresultinreinforcementcorrosion.Theseaspectsarecoveredinmoredetailinlaterchapters.Cracksandcrackpatternshavedifferentcharacteristicsdependingontheunderlyingcause.上一页下一页返回Unit2-3ConcreteCrackingDifferenttypesofcrackoccuratdifferenttimesinthelifeofaconcreteelement(seeTable1).Soaswellasarecognitionofacrackpattern，aknowledgeofthetimeofthefirstappearanceofcracksishelpfulindiagnosingtheunderlyingcause.TheConcreteSociety(1992)providesinformationonthemostcommonformsof“intrinsic"cracksinconcrete.Fig.1(takenfromtheTechnicalReport)illustratesmostofthetypesofcrackthatarelikelytobeexperiencedinthelifetimeofaconcretestructure.上一页下一页返回NewWordsandExpressionsdeformation n.毁坏;变形appropriate adj.适当的，恰当的，相称的flexure n.弯曲;挠曲;弯曲的部分〔地〕单抖挠褶shear n.修剪:剪切变:剪切机torsion

n.扭转.扭曲:扭力.转矩anchorageanchorage n.锚地:锚固:锚具thermal adj.热的;热量的;保暖的moisture n.湿气.潮气:水分:潮湿.湿度oxygen n.氧.氧气chloride n.氯化物corrosion n.腐蚀:侵入:渐失:衰败上一页下一页返回NewWordsandExpressionsintrinsic adj.本身的;本质的;固有的;内在的load-bearing承重的，承载的plasticsettlement塑性沉降carbondioxide二氧化碳上一页下一页返回ExercisesI.TranslatethefollowingwordsandexpressionsintoChinese.1.reinforcedconcrete2.tensilestrength3.cementpaste4.plasticshrinkage5.thermalcontractioncracks上一页下一页返回ExercisesII.Fillintheblankswithsuitablewordsorexpressionsfromthelistgivenbelowandchangetheformwhennecessary.上一页下一页返回ExercisesIII.TranslatethefollowingsentencesintoChinese.1.Microcrackswilldevelopintheconcreteattheinterfacesbetweenthesteelandcementpasteandaggregate，althoughonlyvisiblethroughamicroscope，duetointernalshrinkageetc..2.Ifaconcretebleedsexcessively，thedenserparticlestendtosettleoverembeddedmaterialse.g.thereinforcement，causingthenearsurfacetotear(plasticsettlement)上一页下一页返回Exercises3.Crackscanreducetheshearcapacityofasectionorprovideapathbywhichmoisture，oxygen，carbondioxide，chloridesetc.canpenetrateintotheconcretesurroundingthereinforcementwhichintimemayresultinreinforcementcorrosion.上一页返回Unit2-4DesignPrinciplesofPrestressedConcretePrestressedconcreteisdifferentfromordinary(non-prestressed)reinforcedconcretebecausethetendonsapplyloadstotheconcreteasaresultoftheirprestressforce，whilstinreinforcedconcretethestressesinthereinforcementresultfromtheloadsappliedtothestructure.Aproportionoftheexternalloadsisthereforeresistedbyapplyingaloadintheoppositebysensethroughtheprestressingwhilstthebalancehastoberesistedordinaryreinforcement.下一页返回Unit2-4DesignPrinciplesofPrestressedConcretePrestressingtendonsmaybeinternal，i.e.withintheconcreteeitherbondedtotheconcreteorunbonded,orexternal,i.e.outsidetheconcretebutinsidetheenvelopeofthememberwithprestressedconcretememberswithseeFig.1.Thispaperdealsonlyinternaltendons.Prestressedmemberscanbeeitherpretensioned，i.e.thetendonsarestressedbeforetheconcreteiscastaroundthemandtheforcetransferredtotheconcretewhenithasobtainedsufficientstrength，上一页下一页返回Unit2-4DesignPrinciplesofPrestressedConcreteorpost-tensionedi.e.ductsarecastintotheconcretethroughwhichthetendonsarethreadedandthenstressedaftertheconcretehasgainedsufficientstrength.Table1comparestheadvantagesanddisadvantagesofpre一andpost-tensioning.Precastmemberswillgenerallybepretensionedwiththetendonsbondedtotheconcretewhilstin一situmemberswillbepost-tensionedwiththetendonseitherbondedorunbonded.Table2listsfactorsaffectingthechoiceofbondedorunhondedtendons.上一页下一页返回Unit2-4DesignPrinciplesofPrestressedConcreteWhenaconcretememberisprestresseditwilldeflectandshorten.Ifthetendonprofileissuchthatthedeflectedshapeofthememberiscompatiblewiththerestraintsactingonthemember,theprofileissaidtobeconcordant.Thiswillalwaysbethecaseforastaticallydeterminatemember.However，tendonprofilesinstaticallyindeterminatememberswillnotgenerallybeconcordantseeFig.2.上一页下一页返回Unit2-4DesignPrinciplesofPrestressedConcreteWhenthetendonprofileisconcordant，theforcesinducedatanypointinthememberbytheactionofprestressingareanaxialcompressionequaltotheprestressingforceandamomentequaltotheproductoftheprestressingforceanditseccentricityrelativetotheneutralaxisofthemember.Thesearetheprimaryprestressingforces.上一页下一页返回Unit2-4DesignPrinciplesofPrestressedConcreteWhenthetendonprofileisnon-concordant，additionalforcesandmomentswillbeinducedinthememberduringprestressingbytherestraintsactingonit，seeFig.2.Theseareknownasthesecondaryorparasiticeffects.OtherdefinedincommonnomenclatureassociatedwithprestressedconcreteisFig.3.Concreteisstrongerincompressionthanintension.Prestressisintroducedtopre-compresstheareasofconcretewhichwouldotherwisebeintensionunderserviceloads.上一页下一页返回Unit2-4DesignPrinciplesofPrestressedConcreteTheconcretesectionisthereforestrongerandbehavesmoreasanhomogeneoussection，allowingelasticmethodsof

analysistobeused，althoughtheconcretecompressivestressescanbehigh.Whenthetendonsarebondedtotheconcrete，theirhighultimatestrengthcanbemobilizedwhichgenerallymeansthattheultimateflexuralcapacityofaprestressedconcretememberismuchgreaterthantheappliedultimatedesignmoment上一页下一页返回Unit2-4DesignPrinciplesofPrestressedConcrete.Therefore，limitingthemaximumcompressivestressesandcrackwidthsunderserviceloadsisgenerallycriticalinthedesignofprestressedconcretemembers，althoughthismaynotbethecaseformemberswithunbondedtendons.Therefore，flexuraldesignisnormallycarriedoutattheserviceabilitylimitstateandthencheckedattheultimatelimitstate.Sheardesigniscarriedoutattheultimatelimitstate.上一页下一页返回NewWordsandExpressionsduct n.愉送管;导管grout vt.用薄泥浆填塞n.薄泥浆，水泥浆flexibility n.易曲性;适应性，灵活性;弹性;挠性localise v.使地方化，使限制于局部，确定起源，局限friction n.摩擦;摩擦力deviator n.偏差器;变向装置，致偏器;偏差的事物profile n.侧面(像)，侧影;轮廓，外形;外观，形象;纵断面(图)，剖面(图)上一页下一页返回NewWordsandExpressionsconcordant adj.和谐的，一致的axial adj.轴的，成轴的;绕轴放的eccentricity n.偏心率;偏心距，偏心度;离心率parasitic adj.寄生的;食客的;由寄生物引起的sheath n.护套;护层;叶鞘homogeneous adj.同种的，同类的，相似的;纯一的，均质的;均匀的unbonded adj.无拈结的;未砌合的;无束缚的，自由的，游离的pretensioned先张的上一页下一页返回ExercisesI.TranslatethefollowingwordsandexpressionsintoChinese.1.bondedtendons2.strand3.secondarymoment4.serviceabilitylimitstate5.staticallydeterminatestructure6.externalloads上一页下一页返回ExercisesII.WriteTinfrontofastatementifitistrueandwriteFifitisfalseaccordingtothetext.1.Precastmemberswillgenerallybepost-tensionedwiththebondedtendons.2.Oneoftheadvantagesofpre-tensioningisnoneedforanchorages.3.Concreteisstrongerintensionthanincompression.4.Thereisnoneedtolimitcrackwidthsunderserviceloads.5.Ifthetendonprofileisnon-concordant，theconcretememberisastaticallydeterminatestructure.上一页下一页返回ExercisesIII.TranslatethefollowingsentencesintoChinese.1.Prestressedmemberscanbeeitherpretensioned，i.e.thetendonsarestressedbeforetheconcreteiscastaroundthemandtheforcetransferredtotheconcretewhenithasobtainedsufficientstrength，orpost-tensioned，i.e.ductsarecastintotheconcretethroughwhichthetendonsarethreadedandthenstressedaftertheconcretehaswinedsufficientstrength.上一页下一页返回Exercises2.Theconcretesectionisthereforestrongerandbehavesmoreasanhomogeneoussectionallowingelasticmethodsofanalysistobeused，althoughtheconcretecompressivestressescanbehigh.上一页返回Unit2一5ContractforCivilEngineeringConstructionTheengineershallcarryoutthedutiesspecifiedinthecontract.Theengineermayexercisetheauthorityspecifiedinornecessarilytobeimpliedfromthecontract.Provided，however,thatiftheengineerisrequiredunderthetermsofhisappointmentbytheemployer,toobtainthespecific

approvaloftheemployerbeforeexercisinganysuchauthority，particularsofsuchrequirementsshallbesetoutinthecontract，下一页返回Unit2一5ContractforCivilEngineeringConstructionprovidedfurtherthatanyrequisiteapprovalshallbedeemedtohavebeengivenbytheemployerforanysuchauthorityexercisedbytheengineer.Exceptasexpresslystatedinthecontract，theengineershallhavenoauthoritytorelievethecontractorofanyofhisobligationsunderthecontract.Engineer'sRepresentativeTheengineer'srepresen