软硬岩互层边坡崩塌机理及治理对策研究

JournalofEngineeringGeology1004-9665/2009/17(2)202002063(610059),,,,,,;,60%,,++++,:TD824.7:ACOLLAPSEMECHANISMANDTREATMENTMEASURESOFSLOPESWITHINTERBEDDINGSOFSOFTANDHARDROCKSHUBinHUANGRunqiu(StateKeyLaboratoryofGeoHazardPreventionandGeoEnvironmentProtection,ChengduUniversityofTechnology,Chengdu610059)AbstractSlopecollapseistheprimaryproblemofgeologicalprojectsinslopeswithinterbeddingsofsoftandhardrocksinredbedrockarea.ThispaperexaminesahighwayslopeinsouthwestareaofChina.Thecollapsemecha2nismofformationandthecharacteristicsofstructurearestudiedusingfieldinvestigation.Theslopecharacteristicsoffailureanddeformationaftercollapsearestudiedwiththenonlinearfiniteelementmethodoftwodimensions.Theslopestabilityisalsoevaluatedwithquantitativemethod.Theresultshowsthatowingtothediscrepantweathering,thelowersoftrockmasshassomenotchthatcancausethecollapseandthecracksintheupperhardrockmass.Thecrackslinkupgradually.Ifitisnotstabilizedintime,theupperhardrockmasscancollapsewhenthecracksinthehardrockmasslinkupto60%inthickness.Basedonthecomprehensiveanalysisofthepresentslopestabil2ityandthepotentialpatternoffailureanddeformation,theschemeissettled.Itincludescleaningslopesurface,cuttingpartsoftheslope,hangingthenetofreinforcingbarandsprayedconcrete,reinforcedconcretesupportcol2umn,anddrainagesystem.Thefocaltreatmentmeasureistocontrolthedevelopmentofthecracksintheupperrockmassabovethenotchandtomakewaterproofanddrainestablishment.KeywordsSlopeengineering,Collapse,Mechanism,Stabilityevaluation,Treatmentmeasures,Redbedrock3:2009-01-22;:2009-02-19.:,.Email:[e-mail]1,,,[1,2],20081010,K1+500-K1+600m,(J2s),600m3,,6.9m5.9m4.6m,56m,,,,,,,,,++++22.1,,,80,30m,2030,N6573E/SE1827,42,,(1)2.2:,;,;,,,233,:,N6573E/SE1827,0.8m2.0m,510cm,,1Fig.1Engineeringgeologicalprofileoftheslope;J1,N6286E/NW5767,,,0.61.0m,,,,,;J2,,N1624W/NE8288,,0.30.8m,,N48W/NE74822.32.3.1,,,;,,,,,,,,,,,,,,2.3.2,,;,,,,,,(4)10217(2):2Fig.2Geologicalsketchmapoftheslopesurface3()Fig.3Stereographicpolarprojectionofdominantstructuralplanesandslopesurface3,,,,,4Fig.4Progressivedeformationtypeofdiscrepantweathering,,,2-2,(1)(1)202JournalofEngineeringGeology20091Table1Parameterofrockandsoil/MPa/kPa/()/kNm-342500.303103222.085000.276503924.5120000.22120052.326.37120.326526.521.59800.28782822.511000.2510029.524.542500.30232.528.822.585000.27487.535.125.0120000.22900.049.226.37120.3249.023.822.39800.2858.525.222.511000.2675.026.424.5,,20kPa,;,;,6.5cm(5)5Fig.5Counterof3andverticaldisplacementofsolpeinnaturalcondition,,,14.0cm(6),,;,6Fig.6Counterof3andverticaldisplacementofsolpeinrainycondition4,,,,,,1,,40%50%60%70%80%90%100%,,4:(1);(2)+();(3)+;(4)++,0.1(2),,,:,,60%,;60%,1.00,,,,30217(2):2Table2Stabilityresultofpotentialunstablerockmass+/(%)2.3412.2562.1902.11901.5731.4571.4681.364401.5731.2651.2911.183501.1961.0761.1141.016601.0100.8900.9380.850700.8240.7060.7630.684800.6390.5250.5880.518900.4540.3460.4140.353100,,,60%,5,,:++++(7)(1)+:(2):,,8@2020cm,22@44m,L=4m,C20,10cm;(C20,10cm)(3):,:800mm600mm,:17.58m9.577m,28,L=6m8m:1828,12@400,,,(4):,72-2’Fig.7Distrbutionsketchmapofcontrollingmeasurementsof2-2’profile,228,L=6m(5):90,L=6m;40@44m,L=4m,(6):,12m4,1a6(1),,,;,,,,,,,,,(2),,402JournalofEngineeringGeology2009,,(3),++++[1],.M[J].,2003,11(4):411415.ZhuBaolong,HuHoutianetal..Preliminarystudyonthecharac2terieticandhazardsofM-shapedroadcutslopeinredbeds.JournalofEngineeringGeology,2003,11(4):411415.[2],,,.[J].,2005,13(2):174178.ShaoJiang,LiRencheng,ZhouDepei,etc..Preliminarystudyoftheslipmechanismandthestopingmethodonthelandslideoftheapproximatelyhorizontalexcavatedslopeinredbeds.JournalofEngineeringGeology,2005,13(2):174178.[3],.[J].,2002,(2):5355.ZhengLingzhi,MaHongsheng.NumericalsimulationofunstablerocktreatmentonTaziMountain.HydrogeologyandEngineeringGeology,2002,(2):5355.[4],,,.[J].,2004,23(7):11861192.ShiGuangbin,YangJinghui,AnShengxun,etc.Collapsemecha2nismanalysisofsteep-highrockslopeofshiquanhydropowersta2tionandreinforcementdesign.ChineseJournalofRockMechanicsandEngineering,2004,23(7):11861192.[5],,.[J].,2005,33():412416.JuNengpan,TuGuoxiang,DdengHui.StabilityevaluationonafallingaccumulationinaroadinSichuan.EarthandEnvironment,2005,33(Suppl):412416.[6],,.[M].,1991.HuangRunqiu,ZhangZhuoyuan,WangShitian.Researchonsys2temsengineeringgeologyforstabilityofhighslope.Chengdu:ChengduUniversityofScienceandTechnologyPress,1991.[7],,.[M].:,1994.ZhangZhuoyuan,WangShitian,WangLansheng.Principlesofengineeringgeology.Beijing:GeologicalPublishingHouse,1994.[8].[J].,2007,15(2):253257.ZhengJianzhong.Stabilityassessmentandsupporteffectivenessofhighportalslopeforatwin-archedtunnelinFuxitown,Anhuiprovince.JournalofEngineeringGeology,2007,15(2):253257.[9],.[J].,2007,15(4):559563.YuDehai,PengJianbing.Studyondeformationandfailureprop2ertyofthecuttingslopeinthesouthernShaanxiprovince.JournalofEngineeringGeology,2007,15(4):559563.[10],,.[J].,2008,16(5):592597.BaiYongjian,HuangRunqiu,etal.3DECstabilityanalysisofhighandsteeprockslope.JournalofEngineeringGeology,2008,16(5):592597.50217(2):