SubgradeandPavementZhangGuoguang12125775(ClassMaster1208)SomeBasicKnowledgeof7capitalofradiation9north-southlines18east-westlinesNationalHighwayNetworkLayoutScheme“7918“Networkthetotalsizeofabout85,000km,ofwhich:68,000kmofmainline,regionallink,contactlineandotherroutesofabout17,000km.7capitalofradiation9north-southlines18east-westlinesNationalHighwayNetworkLayoutScheme“7918“NetworkShandongProvinceHighwayNetworkPlanScheme“5418”NetworkRemovetopsoilCompactionoforiginalsurfaceSubgradefillingconstructionbackfillingbehindabutmentBridgeconstructionsubgradetestRockBlastingstoneworkofsubgradefillingconstructionmachineconstructionmachineSubgradesurfaceformationlevel(finishinglevel)PavementConstructionSideditchDrainageFacilitiesCulvertBridgedeckpavementK16+430BridgeprotectionandreinforcementofthehighcuttingslopeMeshReinforcementPlatformBridgeContents1.conceptsofsubgradeandpavement2.testingforsubgrade3.performancerequirements4.pavementtype5.maintenance6.applacations,advantages,disadvantages1.ConceptsofsubgradeandpavementSubgradePavement1.ConceptsofsubgradeandpavementThebasicstructurecross-sectionofhighwayUpperbaseSurfacecourseSubbaseCushionSubgradePavement1.ConceptsofsubgradeandpavementSurfaceCourseSubgradeUpperRoadbedUpperbaseSubbaseUpperlayer(Surfacecourse)MiddlecourseUndercourse30cm50cm70cm20~40cm4~5cm5~6cm6~8cm70~80cmCommonthicknessPavement20~40cmBaseCourseUnderRoadbedUpperEmbankmentUnderEmbankment2.TestingforSubgradeThereareseveraltestingmethodthatwereusedtotestthesubgrade.Thenotableandmostrecommendedtest(amongothers)tobecarryoutareasfollows:CaliforniaBearingRatio(CBR)CompactionTest3.PerformancerequirementsThepavementandsubgrade’sperformancegenerallydependsthefollowingcharacteristics:BearingCapacityStabilityDurabilitySurfaceSmoothnessSurfaceSkidResistance4.PavementTypeBasically,allhardsurfacedpavementtypescanbecategorizedintotwogroups.FlexiblepavementRigidpavement4.PavementType5.MaintenanceFlexiblepavementgenerallyrequiresomesortofmaintenanceorrehabilitationevery10to15years.Rigidpavement,ontheotherhand,canoftenserve20to40yearswithlittleornomaintenanceorrehabilitation.6.1RigidPavementTypicalApplicationsHighvolumetrafficlanesHighwaytohighwayconnectionsExitrampswithheavytraffic6.Applications,Advantages,Disadvantages6.2AdvantagesofRigidPavementGooddurabilityLongservicelifeWithstandrepeatedfloodingandsubsurfacewaterwithoutdeterioration6.Applications,Advantages,Disadvantages6.3DisadvantagesofRigidPavementMaylosenon-skidsurfacewithtimeMayfaultattransversejointsRequiresfrequentjointmaintenance6.Applications,Advantages,Disadvantages6.4FlexiblePavementTypicalApplicationsTrafficlanesAuxiliarylanesRampsParkingareasShoulders6.Applications,Advantages,Disadvantages6.5AdvantagesofFlexiblePavementAdjuststolimiteddifferentialsettlementEasilyrepairedAdditionalthicknessaddedanytimeNon-skidpropertiesdonotdeteriorateQuieterandsmootherToleratesagreaterrangeoftemperatures6.Applications,Advantages,Disadvantages6.6DisadvantagesofFlexiblePavementLosessomeflexibilityandcohesionwithtimeNotnormallychosenwherewaterisexpected6.Applications,Advantages,DisadvantagesZhangGuoguang