摘要
本文基于非饱和渗流理论及非饱和土的Fredlund双应力变量强度理论,对一沿岩土接触面滑动的堆积层滑坡模型,分别进行了8种条件下的降雨入渗数值模拟试验,研究了不同土体渗透性及降雨强度对滑坡稳定性的影响。结果表明:(1)堆积层滑坡的稳定性与土体的渗透性有密切关系,在降雨后的短期内,土体渗透性越好,滑面孔隙水压力升高越明显,滑坡的稳定性降低程度越大;(2)降雨期间,埋深较浅的滑面,入渗雨水能够较快到达,对滑坡稳定性的影响较大;(3)在相同的降雨时间内,降雨强度越大,滑坡稳定性降低速率越快;(4)降雨强度影响着滑坡发生的滞后性,在降雨总量一定的条件下,若降雨强度较大,雨停后,滑坡稳定性继续下降的程度较大;(5)降雨总量控制着滑坡的最终稳定性。
This study was based on unsaturated seepage theory and Fredlund double stress variable strength theory for unsaturated soil. For a slope model of the accumulation layer sliding along the contact surface of the rock and soil,we have conducted numerical simulation tests of rainfall infiltration under eight conditions ,and analyzed the effects of different soil permeability and rainfall intensity on the landslide stability. The results show that the stabil- ity of the accumulation slope is closely related to the permeability of soil. The better soil permeability will cause higher pore water pressure on the sliding surface and cause larger probability of slope failure in the short time since rainfall. The shallower sliding surface can cause infiltration rainfall to arrive the sliding surface quickly and lead to larger probability of slope failure during rainfall. The intense rainfall may reduce landslide stability rapidly under the same rainfall amount. Rainfall controls the backwardness of landslide stability after the end of rain. Under a certain total amount of rainfall, the larger the rainfall intensity is, the landslide stability is more likely to continue to decrease when the rain stops. The total amount of rainfall controls the final landslide stability.
出处
《地质与勘探》
CAS
CSCD
北大核心
2016年第4期743-750,共8页
Geology and Exploration
基金
重庆市教委科技项目(编号KJ1403204)
重庆工程职业技术学院院级课题(编号KJB201512)资助
关键词
渗透性
降雨强度
堆积层滑坡
permeability, rainfall, accumulation landslide
作者简介
[第一作者]覃伟（1981年-），男，2011年毕业于成都理工大学，获硕士学位，助教，主要从事地质灾害教学、研究工作。E-mail：qinw09@163．com。
