降雨入渗对裂隙性粘土边坡稳定性作用机理的分析  

Mechanism analysis on the influence of the rainfall infiltration on the stability of fissured clay slope

作　　者：阙云[1] 胡昌斌[1] 姚晓琴[1] 

机构地区：[1]福州大学土木工程学院,福建福州350108

出　　处：《福州大学学报（自然科学版）》2009年第3期423-429,共7页Journal of Fuzhou University(Natural Science Edition)

基　　金：福建省教育厅科研资助项目(JA08016);福州大学人才基金资助项目(XRC-0814)

摘　　要：为进一步认识降雨入渗对裂隙性粘土边坡稳定性的作用机理,基于饱和-非饱和渗流理论,研究了降雨条件下不同裂隙深度、裂隙开口宽度、裂隙分布位置、降雨强度和降雨持时等对裂隙性粘土边坡渗流场的影响,并进行了相应的稳定性评价.研究结果表明:裂隙的存在改变坡体的入渗能力和入渗路径;裂隙开裂越深,饱和区域越大,边坡稳定性越低;裂隙开口宽度的大小对稳定性的影响不大;裂隙分布在坡顶时易发生浅层破坏,稳定性较低,降雨容易导致浅层破坏,且对裂隙分布坡底边坡稳定性影响大;降雨强度主要影响裂隙层达到饱和的快慢,对于边坡的长期稳定性的影响则可以忽略;裂隙粘土边坡稳定性随降雨持续时间的增加而减小,当裂隙层达到饱和后,其安全系数基本不变.In order to recognize the mechanisms of fissured clay slope with the effect of rain infiltration on stability, the influence factors including fissure depth, width, position, rain intensity and duration on seepage field and stability of fissured clay slope are analyzed based on saturated - unsaturated flow theory. The results of numerical simulation show that fissure is of a great influence on the infiltration capacity and the flow path. The deeper the fissure, the larger the saturated range is. The safety factor of fissured clay slope decreases with the increments of fissure depth. The safety factor of slope is not sensitive with the size of fissure wideth. The position of fissure is affect both the slip - surface and the stability of slope. There is superficial layer failure with low stability when fissure located on the top of slope. Rain infiltration strongly affects the stability when fissure located on the bottom of slope. Rain intensity mainly affects the velocity of the fissure layer to reach at saturated condition. The safety factor of slope decreases with increments of rain duration before the fissure layer reach to saturated condition, then maintain a stable value.

关 键 词：裂隙 粘土 边坡 降雨 入渗 渗流场 稳定 

分 类 号：TU45[建筑科学—岩土工程]