黄土滑坡流滑机理的试验研究  

UNDRAINED CONSOLIDATION TRIAXIAL TEST FOR FLOW SLIDING MECHANISM OF LOESS LANDSLIDES

作　　者：周永习[1] 张得煊[1] 周喜德 

机构地区：[1]上海交通大学土木工程系,上海200240 [2]二滩水电开发责任有限公司,成都610051

出　　处：《工程地质学报》2010年第1期72-77,共6页Journal of Engineering Geology

基　　金：国家自然科学基金资助项目(No-40772187)

摘　　要：饱和黄土的稳态强度(残余强度)是黄土边坡是否发生流滑的关键因素,为了评价饱和黄土的残余强度就需要很好的了解饱和黄土的不排水剪切性能。通过对饱和黄土的固结不排水三轴试验研究了饱和黄土的稳态强度理论。试验研究发现饱和黄土有两种典型的不排水剪切特性:稳态特性、准稳态特性。且大多数情况下饱和黄土总表现为稳态特性,只有疏松的黄土表现出准稳态特性;根据试验结果得出了黄土的稳态线与稳态强度线,可以用来分析黄土边坡的流滑机理。探讨了描述黄土稳态性质的参数内摩擦角和粘聚力的物理含义;比较了由地震引发的滑坡与灌溉诱发的滑坡流滑机理的差异,对于地震引起的黄土滑坡土体残余(稳态)强度起决定性作用,而对于灌溉引起的黄土滑坡土体的峰值强度才是关键因素。The steady state strength（i.e.,residual strength） plays a major role in the flow sliding mechanism of loess landslides.The evaluation of residual strength requires a better understanding of undrained saturated loess behavior.The steady strength of saturated loess is examined using stress-controlled undrained consolidation triaxial test.Two typical stress-strain behaviors of saturated loess are steady state behavior and quasi-steady state.The majority situations exhibit steady state behavior.Only loose loess exhibits quasi-steady state behavior.According to the test results,steady state line and steady state strength line of saturated loess are established.These lines can be used to analyze the mechanism of flow slide.It can use the angle of internal friction and cohesion to describe the steady state behavior of saturated loess.The meaning of these parameters is discussed.The difference of irrigation-induced landslides of loess and seismically-induced landslides of loess is analyzed.If the landslides induced by earthquake,the steady state strength（residual strength） plays a major role.If the landslides induced by irrigation,the peak strength plays a major role.

关 键 词：饱和黄土 流滑 稳态线 稳态强度 三轴试验 

分 类 号：TU443[建筑科学—岩土工程]