路基防护与加固设计课件.ppt

路基防护与加固设计课件.ppt

Sub-gradeProtectionandReinforcementDesignSection1Overview1,thesignificanceofprotectionandreinforcement2,thefacilitiesofprotectionandreinforcementworks 1、slopeprotection 1）plantprotection (1)、seedingNotsteepforgrassgrowthina1:1soilslope(2)、soddingForasteepslope,severeerosion,runoffrateisgreaterthan0.6m/s,theregionnearthegrassembankmentsourceseasier. (3)、planttreesMainfunctionisreinforcingtheslope,topreventandreducewatererosion.2、EngineeringProtection1）PlasteringandPointingJointPlastersuitsforeasilyweatheredsoftrockcutslope.Generallyusedinthelimeslagmortar,stonemortar.Pointingjiontappliestohard,noteasytocrackandmoreweatheredbutthejoints,thinrockslopetopreventdiseasescausedbywaterpenetrationinsidetherock. 2）GroutingandGunitingGroutingappliestohard,localexistenceoflargeanddeepcracksorholes,andfurtherexpansionofslopestabilityborderoftheslope.Gunitingappliestosmoothandeasyweatheringoffreshrockslope.3）AnchorHangingNet（concrete）ProtectionItappliestotheslopeforthefracturedhardrockordiscontinuouslayeredstructurelikerockformationsanddowntheslopeexcavationslope. 4）masonryprotectionTopreventsurfacerunofforrivererosion,roadfillslope,immersionpartsoftheslopealongtheriverembankment,soilcutthelowerpartofthelocalslopeandtheslopenearthebridge,canusemasonryprotection. 5、facingwallFacingwallappliestoweatheringorsevereweatheringandcrushing,landslideeasytoproducedebrisavalancheofrockcuttingslopeorvulnerabletoerosion,poorsoilswellinglargerSlope. Section3Erosionprotection◆DirectprotectionDirectprotectionisameasureofdirectreinforcement,characterizedbylittleornointerferencewiththeflowpropertiesoftheoriginaldisturbance.1RriprapprotectionRiprapprotectionistopreventtheflowofbankerosionorforcestructuresandthelargerstonesfilledprotectivemeasures. 2、GabionprotectionGabionprotectionreferstotheriverbanksorstructurestopreventerosionbywaterandsetacagefilledwithrocks. 3GeomembranebagGeotextilefabricbagsisadoublebag,thebagfilledwithliquidconcreteorcementmortarorthinstoneconcrete,formedaftersolidificationofhighstrengthandstiffnessoftheindurationplate. ◆IndirectprotectionCommontypesofindirectprotectionarediversiondam,shelterbeltsandchangedchannelandsoon.Diversionstructuresaregenerallyspurdike,longitudinaldike,cellulardamandthenecessaryriverchangesproject. Section4SoftgroundconsolidationReplacementsoil、rollingcompaction、drainageconsolidation、vibrationcompaction、chemicalconsolidation。1、Soildistribution：Inourcountryalongtheriverandlakezonewidelyused.2、Features：highwatercontent,badpermeability,highcompressibilitywhenusedforsubgradesoil,itiseasilytocausesettlementorinstability.3、Concept：Itisthesaturatedwaterunderwaterdepositionofsoftclayeysoilsorsiltprimarilystratum,sometimeshaveasmallamountofcorruptionmudorpeatlayer. Consolidationmethods Treatmentprocess Section5subgradedeformationanddemage◆Maindeformation荷载因素：自重、行车荷载、自然因素影响稳定性的因素：水分、温度变化（正温度、负温度）、风蚀作用。变形：弹性的、残留的（不能恢复的）1、subsidence：垂直方向产生较大的沉落 原因：1）填料不当2）填筑方法不合理：①不同土混杂；②未分层填筑、压实；③土中有未经打碎的大块土或冻土块；④荷载、水和温度综合变化；⑤原地面软弱，如泥沼、流沙、垃圾堆积未做处理等；⑥冻胀、翻浆。2、landslide——常见的路基病害，也是水毁的普遍现象⑴slip溜方：少量土体沿土质边坡向下移动而形成。边坡上表面薄层土体下溜。原因：流动水冲刷边坡、施工不当引起。⑵slide滑坡：一部分土体在重力作用下沿某一滑动层滑动。原因：土体稳定性不足引起。 3debrisavalanceandcollapse剥落和碎落：剥落和碎落是指路堑边坡风化岩层表面，大气温度与湿度交替作用以及雨水冲刷和动力作用之下，表面岩石从坡面上剥落下来，向下滚落。大块岩石脱离坡面沿边坡滚落称为崩塌。崩塌：整体岩块在重力作用下倾倒、崩落。原因：岩体风化破碎，边坡较高。影响：危害较大的病害之一。 比较：崩塌无固定滑动面。崩塌体各部分相对位置在移动过程中完全打乱。崩塌滑坡4、subgradeslipping原因：①山坡较陡；②原地面未清除杂草或人工挖台阶；③坡脚未进行必要的支撑。5、subgradedestroycausedbyadversegeologyandhydrology不良地质条件：泥石流、溶洞等。较大自然灾害：大暴雨地区。 ◆Subgradediseasecontrol提高路基稳定性，防止各种病害产生，采取措施：1、正确设计路基横断面。2、选择良好的路基用土填筑路基，必要时对填土作稳定处理。3、采取正确的填筑方法，充分压实路基，保证达到规定的压实度。4、适当提高路基，防止水分从侧面渗入或从地下水位上升进入路基工作区范围。5、正确进行排水设计。6、必要时设计隔离层隔绝毛细水，设置隔温层减少路基冰冻深度和水分累积。7、采取边坡加固、修筑挡土结构物、土体加固等防护技术措施，以提高其稳定性。 Thankyou!Everyone!