非饱和土边坡稳定分析中强度折减法与条分法的比较_李荣建.doc

非饱和土边坡稳定分析中强度折减法与条分法的比较_李荣建 第38卷??第9期 2010年9月西北农林科技大学学报(自然科学版)JournalofNorthwestAamp;FUniversity(Nat.Sci.Ed.)Vol.38No.9Sep.2010非饱和土边坡稳定分析中强度折减法与条分法的比较 李荣建1,郑??文1,邵生俊1,常体鹏2 (1西安理工大学岩土工程研究所,陕西西安710048;2中铁十七局集团第二工程有限公司,陕西西安710043) [摘??要]????目的??对比分析不同基质吸力分布条件下,Bishop条分法和强度折减有限元法计算结果的异同。 ??方法??在考虑非饱和基质吸力条件下,基于Bishop条分法和强度折减有限元法的计算原理和实现方法,开发了可考虑基质吸力的Bishop条分法和强度折减有限元法的相关程序,并且针对某边坡工程进行了计算分析。??结果??在基质吸力逐步减弱直至丧失的过程中,2种方法均在一定程度上反映了非饱和土边坡安全系数降低的现象,但二者确定的安全系数大小有一定差异,且二者确定的潜在滑动面形状和位置差异较大。??结论??相比而言,在较复杂基质吸力分布条件下,强度折减有限元法适用性较好、计算结果较合理,有较大的发展前景。 [关键词]??边坡;稳定性;基质吸力;条分法;强度折减有限元法 [中图分类号]??TU432[文献标识码]??A[文章编号]??1671-9387(2010)09-0207-08 Comparisonanalysesonstabilityofunsaturatedsoil slopesbystrengthreductionFEMandslicemethod LIRong-jian,ZHENGWen,SHAOSheng-jun,CHANGT-ipeng1112 (1InstituteofGeotechnicalEngineering,Xi??anUniversityofTechnology,Xi??an,Shaanxi710048,China; 2The2ndEngineeringCo.LtdofChinaRailway17BureauGroupCorporation,Xi??an,Shaanxi710043,China) Abstract:??Objective??ThecharacteristicanddifferenceoftheresultsoftheslicemethodandstrengthreductionFEMarecomparedunderthecasesofdifferentdistributionsofmatricsuction.??Method??BasedondiscussionofthecomputationalprincipleandmethodofBishop??sslicemethodandthestrengthreduc-tionFEM,theprogramcodesoftheslicemethodandstrengthreductionFEMwhichcanconsidermatricsuctionaredevelopedindividually.??Result??Theresultsshowthattheslopesafetyfactorreducestosomeextentbutdifferentinvaluewiththematricsuctiongraduallyweakeningusingthetwomethods.Inadd-ition,theshapeandpositionofpotentialslidingsurfacedeterminedbythetwomethodshaveagreatdiffer-ence.??Conclusion??ThestrengthreductionFEMwhichcanconsidermorecomplicateddistributionofmatricsuctioncanprovideamorefeasibleandprecisemethodforthestabilityanalysesofunsaturatedsoilslope.???????????????? Keywords:slope;stability;matricsuction;slicemethod;strengthreductionFEM ????非饱和土边坡稳定性的影响因素众多,其中非 均匀分布的基质吸力是影响非饱和土边坡稳定性的 主要因素之一;此外,非饱和土边坡的基质吸力在