滑坡碎屑流运动特征的模型试验研究

运动距离、速度变化及堆积体厚度是滑坡致灾区域和致灾强度的主要评价指标,其复杂的运动机制使灾害预防十分困难。通过开展室内滑坡模型试验,研究了岩土体类型、斜坡坡度和滑体体积对其运动特征的影响。试验结果表明:滑坡碎屑流的运动距离受控于岩土体类型,且随着碎屑粒径的增大而增大。且随着斜坡坡度的增大,滑坡由分级启动向整体启动转变,撞击坡脚引起的持速特征,是造成同等规模下滑坡运动距离和堆积厚度差异的原因。同时,滑坡规模越大,其运动距离越远,符合滑坡的规模效应。

Study of movement characteristics of landslide-debris flow based on model test

The movement distances, velocity variation and accumulative body thickness are the important assessment indicators for evaluation of disaster area and disaster intensity. The complex movement mechanisms make the prediction of this disaster very difficult. A series of laboratory landslide model tests were conducted to analyze the influence of rock mass type, slope gradient and landslide volume on its movement parameters. The experimental results show that the movement distance of the landslide-debris flow is controlled by the rock mass type, which is increased with the increase of debris particle size. With the increase of slope gradient, the landslide changed from stage-starting to whole starting. The speed characteristics caused by the slope toe im-pacting are the cause to the difference of the movement distance and the thickness under the same scale landslide. Meanwhile, the larger the landslide is, the longer the moving distance is, which is consistent with scale effect of landslide.