土的工程绪论土的工程 (215).pdf
8.2 Engineering application of retaining wallEngineering application of retaining wallRetaining walls:Theretainingwallisastructure to support the naturalor artificial slopes and to keep thesoil stable.It is widely used inproject construction,such as civil,bridge,transportation,tunnel,hydraulic,ports,andrailwayengineering.Civil engineering土力学土力学Soil MechanicsSoil MechanicsProf.Prof.H.J.LiaoH.J.LiaoBridgeTransportation土力学土力学Soil MechanicsSoil MechanicsProf.Prof.H.J.LiaoH.J.LiaoTunnelHydraulic土力学土力学Soil MechanicsSoil MechanicsProf.Prof.H.J.LiaoH.J.LiaoThe retaining wall is used to support the slope or backfillaround the building to prevent the slope from collapsing.BuildingBuilding（a）（b）Retaining wallRetaining wallRetaining wallBuildingSlopeBackfillBuilding土力学土力学Soil MechanicsSoil MechanicsProf.Prof.H.J.LiaoH.J.LiaoEngineering caseThe retaining wall can beused as the sidewall of thebasement of the building.（c）SoilRetaining wall（sidewall）（d）The retaining wall is used asthe abutment for connectingembankments and bridges.Retaining wall（abutment）Basement of the buildingTruss bridge土力学土力学Soil MechanicsSoil MechanicsProf.Prof.H.J.LiaoH.J.LiaoThe retaining wall is also used to support the granular material in road or building construction.Retaining wall（e）Retaining wallGranular material土力学土力学Soil MechanicsSoil MechanicsProf.Prof.H.J.LiaoH.J.LiaoExcavation supportSlope anti-sliding support土力学土力学Soil MechanicsSoil MechanicsProf.Prof.H.J.LiaoH.J.LiaoTypes of retaining walls:There are many types of retaining walls,whichcanbeclassifiedaccordingtostructuralforms,buildingmaterials,construction methods,and environmentalconditions.Types of retaining walls土力学土力学Soil MechanicsSoil MechanicsProf.Prof.H.J.LiaoH.J.LiaoAccording to the different structure and stress state ofthe retaining wall,it can be divided into the followingtypes:1.Gravity retaining wallWall topWall faceWall backWall toeWall hellGravity retaining wall土力学土力学Soil MechanicsSoil MechanicsProf.Prof.H.J.LiaoH.J.LiaoGravity retaining walls:Gravity retaining walls are widelyused in engineering.Itcanbeconstructedfromlocalmaterials,such as rockfills or bricks.The height of the wall is not large.The cross-section is large.The wall is stand by its self-weight.If the retaining wall is high.The self-weight of the wall is big.The size of the wall is big.土力学土力学Soil MechanicsSoil MechanicsProf.Prof.H.J.LiaoH.J.LiaoThe settlement and stability problems will appear.Constructed by reinforced concrete material.A light-weight supporting structure.Keep balance via the self-weight and thebackfill on the heel plate of the wall.Composed of three cantilever plates,i.e.,vertical walls,wall toe plates,and wall heelplates.If the wall is very high.The cross-section is small.The slenderness ratio is big.BackfillThe stability is a key problem.2.Cantilevered retaining wallVertical wallsWall toe plateWall heel plateCantilevered retaining wall Made of reinforced concrete.Enhance the bending resistanceof the standing wall.Add a diagonal triangular-shapedbuttress along the longitudinaldirection of the wall.Enhance the stability of the wall.Buttress 3.Buttressed retaining wallButtress Wall face plateWall toeWall heel Buttressed retaining wall土力学土力学Soil MechanicsSoil MechanicsProf.Prof.H.J.LiaoH.J.LiaoCompared with the gravity retainingwall,the cantilevered retainingwall andbuttressed retaining wall has a smaller sizeand lower weight,which is suit for using inthe poor capacity foundations.土力学土力学Soil MechanicsSoil MechanicsProf.Prof.H.J.LiaoH.J.Liao Anchor-pull type retaining structure.Light-weight retaining wall.The tie rod is usually made of thicker hot-rolledsteel bar wrapped with anti-corrosion layer,theend of the steel is connected to an anchor plate,and the head of the steel is connected to the wall.The earth pressure acting on the wall plate istransmitted to the anchor plate through the tierod,and keep balance by the resistance of theanchor plate.Anchor plate retaining walls are generally usedfor backfill.During the filling process,theanchor plates and tie rods are buried in thecompacted soil.4.Anchor plate retaining wallTie rodWall plateAnchor plateBackfillAnchor plate retaining wallWallpanelReinforced materialBackfill(e)Reinforced earth retaining wall A composite structure composed ofthe retaining wall panel,reinforcedmaterial,and backfill.Simple structure and convenient forconstruction Thedeformationconditionandengineering characteristics of the soilare improved by the friction betweenthe reinforcement material and thesoil to stabilize the soil mass.Thereinforcedsoilisaflexiblestructure,and it can adapt to thesmall deformation of the foundation.Wall panelReinforced materialBackfill5.Reinforced earth retaining wallIn addition,there also have several types of retaining walls,such asanchor retaining walls,shotcrete-bolt support,sheet pile retainingwalls,and hybrid retaining walls,etc.,which are commonly used inslope enhancement,tunnel engineering,railway embankment,bridgeabutment,and pit excavation support,etc.Anchor retaining wallsShotcrete-bolt support土力学土力学Soil MechanicsSoil MechanicsProf.Prof.H.J.LiaoH.J.LiaoSlope enhancementTunnel engineering土力学土力学Soil MechanicsSoil MechanicsProf.Prof.H.J.LiaoH.J.LiaoAccording to the different stiffnessand displacement of the retaining wall,it can be divided into three types.Rigid retaining wallThe rigid retaining has higher stiffness and will not deform or haslittle deformation under the action of earth pressure,such as the gravityretaining wall,cantilevered retaining walls,buttressed retaining walls,etc,which are constructed by brick,stone,concrete,reinforced concrete,andother materials.The influence of the wall deformation on the earthpressure distribution can be neglected when calculating the earthpressure of the rigid retaining walls.Rigid retaining wallFlexible retaining wallTemporary supportRigid retaining wallFlexible retaining wallThe flexible retaining wall has low stiffness,andthe wall will produce deformation under the actionof earth pressure,such as anchor plate retainingwall and sheet pile retaining wall.The influence ofthewalldeformationontheearthpressuredistribution should be considered when calculatingthe earth pressure on the flexible retaining walls.Flexible retaining wall土力学土力学Soil MechanicsSoil MechanicsProf.Prof.H.J.LiaoH.J.LiaoEarth pressure:Earth pressure is the lateral pressure of soli onretaining wall.The calculation of earth pressureis an important problem for retaining walldesign.土力学土力学Soil MechanicsSoil MechanicsProf.Prof.H.J.LiaoH.J.LiaoStatementStatement:Thanks for some pictures and materials fromthe Internet used in this courseware only for teaching.
