软硬互层边坡降雨失稳过程力学响应研究  

Mechanical Response Study on Soft and Hard Interbedding Slope Instability During Rainfall

作　　者：李龙起[1] 赵瑞志 王滔 张帅[1] 何川 LI Longqi;ZHAO Ruizhi;WANG Tao;ZHANG Shuai;HE Chuan(State Key Laboratory of Geo-Hazards Prevention&Geo-Environment Protection,Chengdu Univ.of Technology,Chengdu 610059,China)

机构地区：[1]成都理工大学地质灾害防治与地质环境保护国家重点实验室,成都610059

出　　处：《三峡大学学报（自然科学版）》2021年第3期37-41,共5页Journal of China Three Gorges University：Natural Sciences

基　　金：国家自然科学基金资助(41502299);成都理工大学青年骨干计划(KYGG201720)。

摘　　要：为研究缓倾顺层软硬互层岩质边坡在间歇性循环降雨条件下的破坏过程及内部力学响应规律,结合叠加雾化降雨系统,进行了大型室内降雨地质力学物理模拟试验.通过总结强降雨工况下模型边坡内部特殊位置处孔隙水压力的力学响应规律,并依据坡体实际破坏过程监测资料,探究坡体内部力学性质与坡体破坏之间的内在联系.结果表明:间歇性循环降雨是边坡岩体强度及裂隙变化的一个动态损伤过程的诱因,降雨不均匀入渗导致裂隙的不均匀切割效应,致使坡体浅表层不均匀开裂.随着降雨入渗,裂隙不断扩展延伸,岩层面抗剪强度逐渐下降,坡体内部逐渐形成固定的给、排水通道.缓倾顺层软硬互层边坡的破坏模式可概括为3个阶段:前缘切层裂隙贯通-滑移阶段;中-后部岩体拉裂,后部裂隙发育阶段;后缘滑面贯通-失稳阶段.此外,孔隙水压力数值突变时刻较坡体整体失稳时刻提前约6 min,建议可根据孔隙水压力监测数据对软硬互层边坡进行失稳预警.In order to study the failure process and internal mechanical response rule of soft and hard interbedded rock slope with gently inclined bedding under intermittent cyclic rainfall condition,a large-scale geomechanical rainfall modeling test was conducted by using the superposed atomized rainfall system.By summarizing the mechanical response law of pore water pressure at special position inside the model slope under heavy rainfall conditions,and combining the monitoring data of the actual failure process of the slope,the internal relationship between the mechanical properties of the slope and the failure of the slope was explored.The results show that the intermittent cyclic rainfall process is a dynamic damage process of the strength and crack of the slope rock mass,and the uneven cutting effect of the crack is caused by the uneven infiltration of rainfall,resulting in the uneven crack of the slope surface.With the rainfall infiltration,the cracks continue to expand and extend,the shear strength of the rock surface gradually decreases,and a fixed water supply and drainage channel is gradually formed in the slope.The failure mode of soft and hard interbedded slope with gently inclined bedding can be generally summarized as three stages:middle-posterior fracture,posterior fracture development stage and after the edge slip through-instability stage.In addition,the sudden change of pore water pressure is about 6 min earlier than the overall instability of the slope.It is suggested that the failure warning of the soft and hard interbedding slope can be given according to the monitoring data of pore water pressure.

关 键 词：降雨工况 软硬互层边坡 降雨入渗 物理模拟试验 破坏模式 

分 类 号：TU43[建筑科学—岩土工程]