坡脚冲刷作用下近坝库岸边坡滑坡模型试验研究

为研究坡脚冲刷作用对边坡稳定性的影响,基于某水电站近坝库岸边坡滑坡区实测降雨资料,通过自行研制模型试验装置,进行了坡脚冲刷作用下室内边坡滑坡模型试验,分析了坡脚冲刷作用下的边坡滑坡特性。研究表明:坡脚冲刷作用是引起边坡滑坡的主要因素,即:由于强降雨引起河水对边坡侧向产生冲蚀会掏空坡脚的岩土体,且坡脚已冲刷的边坡在降雨作用下不利于边坡稳定,使得边坡失稳下滑会引起边坡滑坡。此时,坡脚处滑坡会不断向边坡上部发展,坡脚冲刷作用下的滑坡以滑动滑坡为主,滑坡类型为浅层牵引式滑坡。

Model experimental study on near-dam reservoir bank slop landslide under slope toe erosion

In order to study the impact from slope toe erosion on the stability of slope，an in-door model experiment on the slope landslide under the impact from slope toe erosion is made through a self-developed model experiment device based on the rainfall data observed within the area of a landslide from the bank near the dam of a hydropower station，and then the slope landslide characteristics under the impact from the slope toe erosion is analyzed herein. The study result shows that the impact from the slope toe erosion is the main factor to cause the slope landslide, i.e. the rock-soil mass of the slope toe is to be eroded at the side of the slope by the river water induced by a strong rainfall，moreover，the slope with the eroded toe is to be unfavorable to the stability of the slope under the impact of rainfall，and then the downward-slide induced by the instability of the slope is to cause a slope landslide. At this time，the landslide at the slope toe is to be continuously developed upward to the upper part of the slope，while the landslide under the impact from the toe erosion is to be mainly the sliding landslide——the type of shallow retrogressive landslide.