文章编号:1000-4750(2023)03-0129-12北疆供水一期工程膨胀性渠坡滑动破坏机制与稳定分析赵凌峰1,2,张凌凯1,2(1.新疆农业大学水利与土木工程学院,新疆,乌鲁木齐830052;2.新疆水利工程安全与水灾害防治重点实验室,新疆,乌鲁木齐830052)cφEcφcφ摘要:北疆供水一期工程属于季节性供水工程,渠道运行多年,渗漏现象严重,渠坡滑动破坏现象频发。为深入探究渠坡的滑动破坏机制,首先对渠基土开展力学特性研究,然后利用其强度特性变化规律对渠坡的不同工况进行数值模拟分析。结果表明:在湿干-冻融循环条件下,膨胀土抗剪强度、值与弹性模量衰减严重,白砂岩值随含水率的增加劣化明显而值基本不变,戈壁料和值受含水率和循环条件影响不显著;通水期间,多次湿干-冻融循环后渠坡均未发生滑动破坏,原因在于渠坡结构面上静水压力的法向分量增加了渠基土沿滑动面的抗滑力,切向分量减少了渠基土沿滑动面的下滑力,提高了渠坡的安全稳定性;停水期间,湿干-冻融循环和膜后水位耦合作用导致渠坡发生滑动破坏,膨胀土性能衰减、白砂岩遇水软化及膜后水位引起孔隙水压力变化是其主要诱因,浅层土体置换、受力结构优化和降低膜后水位能够起到缓解作用;现有排水井对渠坡无抗滑作用,将排水井移至渠坡中部,局部稳定性提升最显著,且单桩保护范围最大,分别为44.3%和45m2。关键词:寒旱区;膨胀土;输水渠道;破坏机制;数值模拟中图分类号:TU443;TV68文献标志码:Adoi:10.6052/j.issn.1000-4750.2021.09.0711SLIDINGFAILUREMECHANISMANDSTABILITYANALYSISOFEXPANSIVECANALSLOPEINNORTHXINJIANGWATERSUPPLYPHASEIPROJECTZHAOLing-feng1,2,ZHANGLing-kai1,2(1.CollegeofHydraulicandCivilEngineering,XinjiangAgriculturalUniversity,Urumqi,Xinjiang830052,China;2.XinjiangKeyLaboratoryofHydraulicEngineeringSecurityandWaterDisastersPrevention,Urumqi,Xinjiang830052,China)Abstract:ThefirstphaseofwatersupplyprojectinnorthernXinjiangbelongstoseasonalwatersupplyproject,andtheleakageofchanneloperationisseriousformanyyears;what'sworse,theslidingfailureofchannelslopeisfrequent.Inordertofurtherexploretheslidingfailuremechanismofcanalslope,themechanicalpropertiesofcanalfoundationsoilarestudied,andthenumericalsimulationanalysisunderdifferentworkingconditionsofcanalslopeiscarriedoutbyusingthevariationlawofitsstr...