《土木工程專業(yè)英語 第2版》 課件 Unit5 Composite Construction；Unit6 Introduction to Foundation Analysis and Design

Unit5CompositeConstructionEnglishforCivilEngineering——Teacher：Prof.ZhengLu（SchoolofCivilEngineering,TONGJIUNIVERSITY）Unit5CompositeConstruction5.1Overview（概述）5.1.1CompositeSteel-ConcreteBeam（鋼-混凝土組合梁）5.1.2CompositeSlabs（組合樓板）5.1.3SteelReinforcedConcrete(SRC)（型鋼混凝土）5.1.4ConcreteFilledTube(CFT)Columns（鋼管混凝土）5.2Pre-stressedConcreteCompositeSlabs（預應力混凝土組合樓板）5.2.1Introduction（簡介）5.2.2OverviewofPre-stressedConcreteCompositePlate（預應力混凝土組合樓板綜述）5.2.3TheResearchandApplicationofPre-stressedCompositeSlabs（預應力組合樓板的研究及應用）5.2.4Conclusion（結論）In1988,BankofChinaTowerinHongKong(Fig.5-1)wascompleted.ThismagnificentbuildingwasthetallestbuildinginAsiaatthattime.Thebuildingwasconstructedusingcompositesteel-concretestructures,whichisanimportantmilestonesincethedevelopmentofthecompositeconstruction.中銀大廈是組合結構史上的里程碑compositesteel-concretestructures鋼-混凝土組合結構；milestone里程碑5.1OverviewCompositeconstructionisamethodofconstructionthatisusedinavarietyofengineeringandbuildingapplications.Employingdissimilarcomponents,suchasconcreteandsteelorfiberglassandfoam,forasingleuseorstructureiscalledcompositeconstruction.Thegoalisunifyingoftheindividualcomponentpropertiestocreateacompositematerialthatpossessesthedesiredpropertiesofallcomponentpieces.組合結構定義dissimilar不同的；fiberglass玻璃纖維；foam泡沫橡膠；unify統(tǒng)一；possess具有5.1OverviewInstructuralengineering,compositeconstructionexistswhentwodifferentmaterialsareboundtogethersostronglythattheyacttogetherasasingleunitfromastructuralpointofview.Whenthisoccurs,itiscalledcompositeaction.Onecommonexampleinvolvessteelbeamssupportingconcretefloorslabs.Ifthebeamisnotconnectedfirmlytotheslab,thentheslabtransfersallofitsweighttothebeamandtheslabcontributesnothingtotheloadcarryingcapabilityofthebeam.However,iftheslabisconnectedpositivelytothebeamwithstuds,thenaportionoftheslabcanbeassumedtoactcompositelywiththebeam.Ineffect,thiscompositecreatesalargerandstrongerbeamthanthesteelbeamalone.Thestructuralengineermaycalculateatransformedsectionasonestepinanalyzingtheloadcarryingcapabilityofthecompositebeam.如何實現(xiàn)組合作用concretefloorslabs混凝土樓板；stud鉚釘；beassumedto假定為；stud鉚釘5.1OverviewCommonstructuralmembersofcompositeconstructioninclude①Steel-ConcreteCompositeBeams(Steel-ConcreteFloorCompositeStructure),②CompositeSlabs,③SteelReinforcedConcrete:SteelReinforcedBeams,SteelReinforcedColumns,SteelReinforcedWalls,④ConcreteFilledTube.組合結構分類5.1OverviewCompositesteel-concretebeamismadeupofsteelbeamandslabbyshear

connector.Inthistypeofcompositebeam,concreteandsteelbeamhavejointstressandcompatibilityofdeformation,whichmakefulluseofthecompressivestrengthofconcreteandthetensilestrengthofsteel.Soitremarkablyraisesthestiffnessandstabilityofbeams.鋼-混凝土組合梁的組合形式shear

connector剪力連接鍵；joint共同的5.1.1CompositeSteel-ConcreteBeamCompositesteel-concretebeamshavebeendevelopedveryfastinrecentyears,andmoreandmorewidelyusedasthehorizontalelementscarryingheavyloadsinbuildingsandbridges,obtainingnotableeconomicandsocialbenefits.組合結構定義horizontalelements水平構件5.1.1CompositeSteel-ConcreteBeamAdvantagesofcompositebeams:1. Theconcreteandsteelisutilizedeffectively.2. Moreeconomicalsteelsectionisusedincompositeconstructionthanconventionalnon-compositeconstructionforthesamespanandloading.3. Depthandweightofsteelbeamrequiredisreduced.So,theconstructiondepthalsoreducesincreasingtheheadroomofthebuilding.組合梁的優(yōu)點utilize利用；conventional傳統(tǒng)的；headroom凈空5.1.1CompositeSteel-ConcreteBeam4. Compositebeamshavehigherstiffness,thustheyhavelessdeflectionthansteelbeams.5. Compositebeams(Fig.5-2)cancoverforlargespacewithouttheneedofanyintermediatecolumns.6. Compositeconstructionisfasterbecauseofusingrolledsteelandpre-fabricatedcomponentsthancast-in-situconcrete.7. Encasedsteelbeamhavehigherresistancetofireandcorrosion.組合梁的優(yōu)點intermediatecolumns中柱；rolledsteel軋制鋼；pre-fabricatedcomponents預制構件；cast-in-situconcrete現(xiàn)澆混凝土；encasedsteelbeam內(nèi)置鋼梁；corrosion腐蝕5.1.1CompositeSteel-ConcreteBeamCompositeslabscommonlyreferstosteeldeckreinforcedcompositeslabs(Fig.5-3)whichareformedbypouringconcreteonthesteelplateofdifferentkindsofconcaveandconvexribsordifferentkindsgrooves.Theyrelyonvariousformsofconcaveandconvexribsorgroovesandthensteelandconcretewillbeconnectedtogether.組合板steeldeck鋼板；concaveandconvexribs凹凸肋；groove凹槽5.1.2CompositeSlabsSteelreinforcedconcrete(Fig.5-4)compositestructures(shortastheSRCcompositestructure)ismadeupofprofilesteel,longitudinalreinforcement,stirrupsandconcrete.Thatisconcretestructurewithprofilesteelinthecoreofstructurecomponentsandwithstirrupsandappropriate

verticalreinforcementoutofstructurecomponents.Itisdividedintotwotypesofstructure:allstructurecomponentsaresteelreinforcedconcretecompositestructuresandpartofstructurecomponentsaresteelreinforcedconcretecompositestructures.型鋼—鋼筋混凝土組合結構的組成成分profilesteel型鋼；longitudinalreinforcement縱向鋼筋；stirrup箍筋；appropriate適量的；verticalreinforcement豎向鋼筋（應為縱向鋼筋）；5.1.3SteelReinforcedConcrete(SRC)Concrete-filledtubecolumnsconsistofasteeltubefilledwithconcrete.Theconcretecoreaddsstiffnessandcompressivestrengthtothetubularcolumnandreducesthepotentialforinwardlocalbuckling.Conversely,thesteeltubeactsaslongitudinalandlateralreinforcementfortheconcretecorehelpingittoresisttension,bendingmomentandshearandprovidingconfinementfortheconcrete.鋼管混凝土柱的組成及優(yōu)點inwardlocalbuckling向內(nèi)的局部屈曲；lateralreinforcement側向支承；confinement約束5.1.4ConcreteFilledTube(CFT)ColumnsDuetothebenefitofcompositeactionofthetwomaterials,theCFTcolumnsprovideexcellentseismiceventresistantstructuralpropertiessuchashighstrength,highductilityandlargeenergyabsorptioncapacity.Also,circularhollowsectionspossessmanyadvantagesoveropensections,includingaestheticappearanceandeconomyintermsofmaterialcosts.鋼管混凝土柱抗震性能好ductility延性；aestheticappearance美觀5.1.4ConcreteFilledTube(CFT)ColumnsDuetothecomplexityofconnectionsbetweensteelbeamsandcircularhollowsections,theiruseinstructuralsteelworkislimited.Thisisbecausetheuseofstandardboltingisnotfeasibleandcostlyunpopularweldedconnectionsarethenormalsolutions.Concrete-filledsteeltube(CFT)columnscombinetheadvantagesofductility,generallyassociatedwithsteelstructures,withthestiffnessofaconcretestructuralsystem.鋼管混凝土柱同時具有鋼結構和混凝土兩種材料的優(yōu)點，不過不能使用常規(guī)螺栓進行連接feasible可行的5.1.4ConcreteFilledTube(CFT)ColumnsInallkindsoffloors,concreteslabsoccupythedominantposition.Concreteslabscanbedividedintotwomajorcategories,thecast-in-placeslabandtheprecastslab.Thecast-in-placeslabhasgoodstructuralintegrity,however,itneedson-siteconcretepouringprocedure,largeconcretewetconstruction,instableconstructionquality,morescaffoldingandtemplates,highcostsandlongconstructionperiod.Theprecastslabisproducedinthefactoryandhasadvantagesoflessconcretewetconstruction,stableconstructionquality,lessscaffoldingandtemplates,lowconstructionnoise,reducibleengineeringcostandshortconstructionperiod.Butitsstructural

integrityneedstobeimproved.Therefore,compositeslabswhichcombinetheadvantagesofcast-in-placeslabsandprecastslabsbecomepopular.Itsbottompanelismanufacturedinfactoryandassembledonthespot.Thentheconcreteispouredinplacetoformthecompositeslab.Thisslabisprovidedwithadvantagesofgoodstructuralintegrity,lessscaffoldingandtemplates,shortconstructionperiod,goodeconomicefficiency,soithaspromisingdevelopmentprospects.組合樓板結合了現(xiàn)澆板和預制板優(yōu)點dominantposition主導地位；category類別；on-siteconcretepouringprocedure現(xiàn)場混凝土澆筑；scaffolding腳手架；template模板；structuralintegrity結構完整性；bottompanel底板；spot現(xiàn)場5.2.1IntroductionThecompositeslabwithpre-stressedbottompanelisthemostwidelyusedcompositeslab.InChina,thepre-stressedthinslabwasproducedupto1957.In1970s,thepre-stressedcompositebeamandslabwasproducedwithcold-drawnlow-carbonsteelwires.In1980s,thestandarddrawingofpre-stressedcompositeslabswascompiled.Nowadays,thecompositeslabhasbeenwidelyusedinthehousingconstruction.Integratedprefabricatedhyperstaticstructureswithcompositecomponents,formedbypre-stressedcompositeslabsandpre-stressedhollowcompositebeams,havebeenappliedintallbuildings.組合板的發(fā)展cold-drawnlow-carbonsteelwires冷拔低碳鋼絲；standarddrawing標準圖冊；compile編制；integratedprefabricatedhyperstaticstructures整體預制的超靜定結構；pre-stressedhollowcompositebeams預應力空心組合梁5.2.2OverviewofPre-stressedConcreteCompositePlateThebottompanelofcompositeslabsmostlyemploysthefirst-tensionedpre-stressedpanel.Thebottompanelcanalsobeusedaspermanentformworks.Accordingtowhetherornotthebracesaresetunderbottompanels,thecompositeslabcanbesortedintoone-stageloadingcompositeslabandtwo-stageloadingcompositeslab.組合板分類first-tensionedpre-stressedpanel先張拉預應力板；permanentformworks永久性模板；one-stageloadingcompositeslab一階段加載組合板；two-stageloadingcompositeslab兩階段加載組合板5.2.2OverviewofPre-stressedConcreteCompositePlateTheone-stageloadingcompositeslabhasslenderbottompanel,soitshouldbesupportedbytemporarybracesbeforethebottompanelsareassembled.Thepost-pouredconcretelayerandbottompanelbegintoworktogetherafterpost-pouredconcreteishardened.Theone-stageloadingcompositeslabissimilarwiththecast-in-placeslabinmechanicalbehavior.一階段加載組合板的做法及特點temporarybraces臨時支撐；bottompanels底板5.2.2OverviewofPre-stressedConcreteCompositePlateThebottompaneloftwo-stagecompositeslabhasenoughbendingstiffnessandneedsnotemporarybracesduringconstruction.Soconstructiondurationcanbeshortenedandtheprojectcostcanbereduced.Differentfromthecast-in-placeslab,thecross-sectiondimensionsandreinforcementsofthecompositeslabaredecidedbyconstructionstage,notbyservicestage.Beforethepost-pouredconcretelayerishardened,itbearsnoloads.Inthemeanwhile,thebottompanelitselfbearsitsdeadweight,post-pouredconcrete’sdeadweightandconstructionloads.Afterthepost-pouredconcretelayerishardened,itbeginstoworktogetherwithbottompaneltoformcompositeslab,whichbearsthedeadweightofpost-pouredconcretelayer,floorsurfaceandceilingandliveloadduringservicestage.兩階段加載組合板的做法及特點cross-sectiondimensions截面尺寸；reinforcement配筋5.2.2OverviewofPre-stressedConcreteCompositePlateThebottompanelpatterndeterminesthebondingbehaviorofthecompositeslabandtheedgejointdetailsinfluencesitscrackresistance.Theroughnessofbottompanelsurfacecanaffectthebondforceofcompositeslabs.Accordingtoroughness,thebottompanelcanbedividedintonaturalroughbottompanel,artificialroughbottompanelandshear-resistantreinforcedbottompanel.Accordingtocrosssection,thebottompanelcanbeclassifiedintoflatbottompanel,precastribbedbottompanel,hollowbottompanelandsandwichbottompanel.組合板根據(jù)底板粗糙程度和截面形狀分類bottompanelpattern底板形狀；bondingbehavior粘結性能；crackresistance抗裂性能5.2.3TheResearchandApplicationofPre-stressedCompositeSlabsCompositeslabwithflatbottompanel.Thebottompanelofthecompositeslabwithflatbottompanelispretensionedprestressedsolidslab,whichistheearliesttypeofcompositeslab.平底板混凝土組合板pretensionedprestressedsolidslab先張法預應力實心板5.2.3TheResearchandApplicationofPre-stressedCompositeSlabsThecompositeslabwithflatbottompanelhasinadequatestructuralintegrity.Itsbondperformanceandcrackresistanceofedgejointdetailsneedtobeimproved;thecompositeslabwithbartrussreinforcedprecastconcretebottompanelhasenoughbondforce,butitsstorageandtransportationareinconvenient;theconcretecompositeslabwithprecastribbedpanelhasgoodstructuralintegrityandconvenientconstructionprocedure;thecompositeslabwithhollowbottompanelandthecompositeslabwithsandwichbottompanelhavethefunctionofsoundinsulationandthermalpreservation,howevertheyareinadequatetoresistbendingmomentandhavecomplexconstructionprocedure.Itisconsideredinthispaperthatamongcompositeslabsmentionedabove,theconcretecompositeslabwithprecastribbedpanelhasmoreadvantagesforimprovement.各種形式的組合板的優(yōu)缺點總結inadequate不足的；bartrussreinforced桁架鋼筋；precastribbedpanel預制肋形板；sandwichbottompanel夾心底板；soundinsulationandthermalpreservation隔聲保溫5.2.4ConclusionUnit6IntroductiontoFoundationAnalysisandDesignEnglishforCivilEngineering——Unit6

IntroductiontoFoundationAnalysisandDesign

6.1Foundations-definitionandPurpose(基礎的定義和用途）6.2FoundationClassifications（基礎的分類）6.3FoundationSiteandSystemEconomics(基礎選址和系統(tǒng)經(jīng)濟）6.4GeneralRequirementsofFoundations（基礎的一般要求）6.5FoundationSelection（基礎的選擇）6.6SIandFPSUnits（SI和FPS單位）

6.7ComputationalAccuracyVersusDesignPrecision（計算精度與設計精度）Allstructuresdesignedtobesupportedbytheearth,includingbuildings,bridges,earthfills,andconcretedams,consistoftwoparts.Thesearethesuperstructure,orupperpart,andthesubstructureelementwhichinterfacesthesuperstructureandsupportingground.Inthecaseofearthfillsanddams,thereisoftennotaclearlineofdemarcationbetweenthesuperstructureandsubstructure.Thefoundationcanbedefinedasthesubstructureandthatadjacentzoneofsoiland/orrockwhichwillbeaffectedbyboththesubstructureelementanditsloads.基礎的定義fills

填土；dams

大壩；substructure

下部結構；interfaces

相互作用；demarcation

界限；adjacent

相鄰的

6.1Foundations-definitionandPurpose

Thefoundationengineeristhatpersonwhobyreasonofexperienceandtrainingcanproducesolutionsfordesignproblemsinvolvingthispartoftheengineeredsystem.Inthiscontext,foundationengineeringcanbedefinedasthescienceandartofapplyingtheprinciplesofsoilandstructuralmechanicstogetherwithengineeringjudgment(the“art”)tosolvetheinterfacingproblem.Thefoundationengineerisconcerneddirectlywiththestructuralmemberswhichaffectthetransferofloadfromthesuperstructuretothesoilsuchthattheresultingsoilstabilityandestimateddeformationsaretolerable.Sincethedesigngeometryandlocationofthesubstructureelementoftenhaveaneffectonhowthesoilresponds,thefoundationengineermustbereasonablyversedinstructuraldesign.基礎工程師的定義mechanics

力學；stability

穩(wěn)定性；estimated

估計；tolerable

可容忍的；6.1Foundations-definitionandPurpose

6.1Foundations-definitionandPurpose

Itisnowrecognizedthatbothsoilstabilityanddeformationaredependentonthestresshistoryofthemass.Ithasbeencommonuntilrecentlytoassociatefoundationengineeringsolelywithsoilmechanicsconcerns,leavingtheinterfacingelementstothestructural(orother)designer.Currenttrendsaretorecognizethatfoundationengineeringisasystemsproblemandcannotbenicelycompartmentalizedassomepersonswouldprefer.Readersmaydeterminethevalidityofthisstatementastheyprogressthroughthetext.基礎是整體結構的一部分solely

單獨的；

trends

趨勢；

compartmentalized

區(qū)別；validity

正確性；6.1Foundations-definitionandPurpose

Thescienceofsoilmechanicsanditsrelationshiptogeologicalprocesseshasprogressedconsiderablyoverthepastfiftyyears.However,becauseofthenaturalvariabilityofsoilandtheresultingproblemsassociatedwithtesting,thedesignofafoundationstilldependstoalargedegreeupon“art”,ortheapplicationofengineeringjudgment.

Asubsetofthisapplicationistheassessmentofthetolerableriskassociatedwiththefoundation.基礎設計有不確定性geological

地質(zhì)學；progressed

發(fā)展；variability

變化性；

assessment

估計；6.1Foundations-definitionandPurpose

Theprimaryfocusofthistextwillbeonanalysisanddesignoftheinterfacingelementsforbuildingsandretainingstructuresandthosesoilmechanicsprinciplesparticularlyapplicabletotheseelements.Theseinterfacingelementsincludebothnearsurfacememberssuchasfootingsandmatsanddeepelementssuchaspilesandcaissons.Retainingstructuresofconcrete(commonlytermedretainingwalls)andmetal(assheetpiling)areconsideredinlaterchapters.Soilmechanicsprinciplesincludebothstability,includingsoilwatereffects,anddeformationanalyses.Soilstabilitycanoftenbeenhancedbyvariousimprovementtechniques,themostcommonbeingcompaction.本文關注重點retainingwalls

擋土墻；metal

金屬；enhanced

加強；compaction

壓實；6.2FoundationClassifications

Foundationsforstructuressuchasbuildings,fromthesmallestresidentialtothetallesthigh—rise,andbridgesareforthepurposeoftransmittingthesuperstructureloads.Theseloadscomefromcolumn—typememberswithstressintensitiesrangingfromperhaps140MPaforsteelto10MPaforconcretetothesupportingcapacityofthesoil,whichisseldomover500kPabutmoreoftenontheorderof200to250kPa.Thereadercanreadilynotethatthisinterfaceconnectsmaterialswhosedifferencesinusefulengineeringstrengthcanvarybyafactorofseveralhundred.交界面材料強度的差距residential

住宅樓；transmitting

傳遞；intensities

強度；readily

容易的；6.2FoundationClassifications

Typicalfoundationtypesare:Foundationsforbuildings(eithershallowordeep)Foundationsforsmokestacks,radioandtelevisiontowers,bridgepiers,industrialequipment,etc.(eithershallowordeep)Foundationsforportormarinestructures(maybeshallowordeepandwithretainingstructuresextensivelyused)Foundationsforrotating,reciprocating,andimpactmachinery,andforturbines,generators,etc.(eithershallowordeepandmayrequirevibrationcontrol)典型基礎的種類smokestacks

煙囪；reciprocating

往復的；turbines

渦輪機；generators

發(fā)電機；Abuildingfoundationmustbeadequateifthestructureistoperformsatisfactorilyandbesafeforoccupancy.Otherfoundationsmustbeadequatetoperformtheirintendedfunctionsinasatisfactoryandsafemanner;however,buildingsusuallyhavemorestringentcriteriaforsafetyandperformancethanotherstructures—notableexceptionsbeingnuclear—plantfacilities,turbinesforpowergeneration,andcertaintypesofradio—antennaequipment.Foundationsfornuclearplantsrequireextremelyrigiddesign/performancecriteriaforsafetyreasons.Theotherfoundationssupportextremelyexpensivemachinerywhichisoftenverysensitivetosmallsoildeformations.不同結構基礎設計要求不同satisfactorily

令人滿意的；occupancy

居??；stringent

嚴格的；notable

值得注意的；6.3FoundationSiteandSystemEconomics

6.3FoundationSiteandSystemEconomics

Morerecently,andafterlossoflifefromseveralavoidablefailures,damdesignswheresoilistheprincipalconstructionmaterialarebeingmorecarefullymade.Onemightnotethatmoreprinciplesofsoilmechanicsandgeologyapplytoearthdamsthantothemajorityoffoundationengineeringproblems.Inadditiontothestringentcriteriaofthesuperstructure,instabilityandwaterflowthroughthebasesoilareseriousconsiderations.Afurtherareaofconcernistheinevitabledeformationofthebasesoilandsubsidenceinthesuperstructure(damfillmaterial).大壩的設計受到重視avoidable

可避免的；inevitable

不可避免的；subsidence

下沉；6.3FoundationSiteandSystemEconomics

Almostanyreasonablestructurecanbebuiltandsafelysupportedifthereisunlimitedfinancing.Unfortunately,intherealsituationthisisseldom,ifever,thecase,andthefoundationengineerhasthedilemmaofmakingadecisionundermuchlessthantheidealcondition.Also,eventhoughthemistakemaybeburied,theresultsfromtheerrorarenotandcanshowuprelativelysoon—andprobablybeforeanystatuteoflimitationsexpires.Therearereportedcaseswherethefoundationdefects(suchascrackedwallsorbrokenmechanicalfixtures)haveshownupyearslater—alsocaseswherethedefectshaveshownupeitherduringconstructionofthesuperstructureorimmediatelythereafter.工程造價限制帶來的問題dilemma

困境；statute

條例；expires

期滿；defects瑕疵；thereafter

從那以后6.3FoundationSiteandSystemEconomics

Sincethesubstructureisburied,orisbeneaththesuperstructure,insuchaconfigurationthataccesswillbedifficultshouldfoundationinadequaciesdevelopafterthesuperstructureisinplace,itiscommonpracticetobeconservative.Aoneortwopercentoverdesignintheseareasproducesalargerpotentialinvestmentreturnthaninthesuperstructure.

基礎的保險設計beneath

在…下方；configuration

配置；conservative

保守的；overdesign

保險設計；investment

投入6.3FoundationSiteandSystemEconomics

Thedesignerisalwaysfacedwiththequestionofwhatconstitutesasafe,economicaldesignwhilesimultaneouslycontendingwiththeinevitablenaturalsoilheterogeneityatasite.Nowadaysthatproblemmaybecompoundedbylandscarcityrequiringreclamationofareaswhichhavebeenusedassanitarylandfills,garbagedumps,orevenhazardouswastedisposalareas.

基礎選址存在的問題constitutes

在…下方；simultaneously

配置；heterogeneity

不均勻性；compounded

組成；reclamation

回收；hazardous危險的6.3FoundationSiteandSystemEconomics

Thefoundationengineermustlookattheentiresystem:thebuildingpurpose,probableservice—lifeloading,typeofframing,soilprofile,constructionmethods,andconstructioncoststoarriveatadesignthatisconsistentwiththeclient/owner’sneedsanddosenotexcessivelydegradetheenvironment.Thismustbedonewithasafetyfactorwhichproducesatolerableriskleveltoboththepublicandtheowner.基礎設計考慮整個系統(tǒng)的建設profile

剖面；consistent

一致；client

客戶；degrade

降級6.3FoundationSiteandSystemEconomics

Consideringtheseseveralareasofuncertainly,itfollowsthatriskandliabilityinsuranceforpersonsengagedinfoundationengineeringisverycostly.Inattemptstoreducethesecostsaswellasproduceadesignwhichcouldbeobtainedfromseveralengineeringfirms(i.e.a“consensus”design)thereisactivediscussion(andthepracticehasalreadybeenundertakeninseveralareas)ofhavingthefoundationengineersubmittheproposeddesigntoaboardofqualifiedengineersfora“peerreview.”

風險和責任保險liability

責任；undertaken

一致；submit

提交；peer

同行Afoundationmustbecapableofsatisfyingseveralstabilityanddeformationrequirementssuchas:Depthmustbeadequatetoavoidlateralexpulsionofmaterialfrombeneaththefoundation—particularlyforfootingsandmats.Depthmustbebelowthezoneofseasonalvolumechangescausedbyfreezing,thawing,andplantgrowth.Systemmustbesafeagainstoverturning,rotation,sliding,orsoilrupture(shear—strengthfailure).基礎的要求expulsion

排擠；seasonal

季節(jié)的；thawing

融化；sliding

滑動；rupture破裂6.4GeneralRequirementsofFoundations

6.4GeneralRequirementsofFoundations

Systemmustbesafeagainstcorrosionordeteriorationduetoharmfulmaterialspresentinthesoil.Thisisaparticularconcerninreclaimingsanitarylandfillsandsometimesformarinefoundations.Systemshouldbeadequatetosustainsomechangesinlatersiteorconstructiongeometry,andbeeasilymodifiedshouldlaterchangesbemajorinscope.Thefoundationshouldbeeconomicalintermsofthemethodofinstallation.Totalearthmovements(generallysettlements)anddifferentialmovementsshouldbetolerableforboththefoundationandsuperstructureelements.Thefoundation,anditsconstruction,mustmeetenvironmentalprotectionstandards.基礎的要求sustain

排擠；modified

修改；installation

安裝；movements

運動；settlements沉降6.5Foundationsselection

基礎種類和適用土壤條件Spreadfooting

擴展基礎；

stratum

層；

differential不均勻；

consolidation

固結；FoundationtypeUseApplicablesoilconditionsSpreadfooting,wallfootingsIndividualcolumns,walls,bridgepiersAnyconditionswherebearingcapacityisadequateforappliedload.Mayuseonsinglestratum:firmlayeroversoftlayerorsoftlayeroverfirmlayer.Checkimmediate,differential,andconsolidationsettlements.FoundationtypeUseApplicablesoilconditionsSpreadfooting,wallfootingsIndividualcolumns,walls,bridgepiersAnyconditionswherebearingcapacityisadequateforappliedload.Mayuseonsinglestratum:firmlayeroversoftlayerorsoftlayeroverfirmlayer.Checkimmediate,differential,andconsolidationsettlements.

基礎類型用途適用的土壤條件

擴展基礎，墻基礎獨立柱，墻壁，橋墩

承載力足以滿足所施加載荷的任何情況?？梢栽趩我煌翆由鲜褂茫河矊由细曹泴踊蜍泴由细灿矊?。需驗算短期，局部以及總沉降。6.5Foundationsselection

6.5Foundationsselection

基礎種類和適用土壤條件Spreadfooting

閥板基礎；

basement地下室；

Corrosive

腐蝕性的；MatfoundationSameasspreadandwallfootings.Veryheavycolumnloads.UsuallyreducesdifferentialsettlementsandtotalsettlementsGenerally,soilbearingvalueislessthanforspreadfootingsoverone-halfareaofbuildingcoveredbyindividualfootings.Checksettlements.PilefoundationsFloatingIngroups(atleast2)tocarryheavycolumn,wallloads;requirespilecapPoorsurfaceandnearsurfacesoils.Soilsofhighbearingcapacity20-50mbelowbasementorgroundsurface,butbydisturbingloadalongpileshaftsoilstrengthisadequate.Corrosivesoilsmayrequireuseoftimberorconcretepilematerial.

MatfoundationSameasspreadandwallfootings.Veryheavycolumnloads.UsuallyreducesdifferentialsettlementsandtotalsettlementsGenerally,soilbearingvalueislessthanforspreadfootingsoverone-halfareaofbuildingcoveredbyindividualfootings.Checksettlements.PilefoundationsFloatingIngroups(atleast2)tocarryheavycolumn,wallloads;requires