降雨型堆积体滑坡大尺寸模型试验

Large-Scale Model Test on Rainfall Induced Colluvium Slope Failure

以堆积体坡为研究对象,进行了大尺寸模型边坡试验,研究了降雨条件下堆积体边坡渗流、变形、破坏的规律,探讨了声发射作为预警的判据.结果表明:浸润面到达后水的体积分数持续增加,增加到峰值后,地下水水位才开始增高.坡顶的位移较大,坡趾的位移较小,位移的增大有一个加速过程.在滑坡启动的瞬间,倾斜角突然增大,加速过程极短.边坡失稳过程中声发射撞击数先缓慢上升再急剧上升.边坡失稳与坡面径流和细粒迁移密切相关.

A large-scale colluvium model test was conducted on rainfall induced slope failure to investigate the laws of the seepage,deformation and failure of colluvium slope under rainfall conditions.Acoustic emission as a criterion of warning was discussed.Results showed that after the wetting front has reached the corresponding measuring point,the volume fraction of water increases continually,and the water level begins to increase untill the volume fraction of water reaches its peak value.The displacement at the top of the slope is large and is small at the toe,and the increase of the displacement of the slope has an acceleration process before failure occurs.The tilt angle increases suddenly when failure occurs.The acoustic emission accounts increase slowly at first and sharply afterwards.Slope failure is strongly linked to surface runoff and fine particle migration.