颗粒级配与场地条件对滑坡运动特征的影响模型试验研究

Model Test Study on Influence of Gradation and Field Condition on Landslide Characteristics

本文运用滑坡模型试验研究了不同坡角和颗粒级配对滑坡运动的影响机制。试验结果表明:坡角对滑坡前缘具有显著的阻止作用,坡角越大,坡脚前后的速度差越大,能量损失越大;滑坡运动到坡脚后,呈现出持速运动特征,持速阶段的运动距离随坡角的增加而增加,但其平均运动速度则在坡角45°时达到最大值;滑坡运动过程分为明显的加速运动、持速运动和耗散减速运动3个阶段;在同一坡角条件下,中值粒径越大的岩土体经过坡脚作用后,阻止效应越不敏感,能量损失越少,能量传递的有效性越大,持速运动的距离越大。

In this paper,the influences of slope and gradation on landslide movement were analyzed based on model test.The test results show that the slope angle of landslide has an significant effect on the front edge of landslide.Larger slope angle leads to larger velocity difference before and behind the toe,and larger energy loss.The velocity stays at a level while the landslide moves to the toe.The distance at this stage increases with the slope angle,while the average velocity reaches its maximum at 45° slope angle.The entire landslide includes three stages：accelerated movement,constant-speed movement and decelerated movement.Under the condition of the same angle,if the median diameter of grain is larger,the prevention from the toe and the loss of energy will be less,energy transfer will be more effective and the distance of constant-speed movement will be longer.