排土场破坏过程及稳定性模型试验研究

设计了一套排土场模型试验装置，利用自然分选形成排土体模型，通过抬高模型一侧来使边坡发生破坏。试验结果表明，滑面近乎为直线，排土体的初始破坏位置集中在1/2～3/4高度处。初始破坏发生后，会引发上部土体的滑动，且破坏规模更大；下滑的土体从1/2高度处开始堆积，随高度降低，堆积的土体增多。下滑的土体由两部分组成，大部分为初始破坏及牵引的上部土体，少部分为下滑过程中带动的坡面土体；基础边坡角越大，破坏发生的范围越大。不同滑面反演出的φ值较为接近，平均值为33.2°，标准差为0.96°；利用反演参数计算的滑后边坡安全系数较为接近，平均值为1.12，标准差为0.015，表明此时边坡均有10%~14%的安全储备。因模拟排土料的石料干燥且粒径均匀，边坡破坏过程与前人研究结果差异较大，模型试验所得结果适用于无地下水条件的碎石边坡。

Model Test Study on Failure Process and Stability of Dump Site

A device related with waste dump model test has been developed, with which natural selection process is adopted to generate the dump site, and slope failure is achieved by raising one side of the devices.The results demonstrate that sliding surface is nearly a straight line, and initial failure position concentrates on 1/2～3/4 height of the dump body.Upper position failure is very likely to happen after initial collapse, with a larger scale.Failure dump start to accumulate at the height of 1/2, with a raising amount when height reduces.It consists of two parts, one part is from the initial damage and the towed upper dump, which occupies most of the weight, and the other part is driven by the decline in the process of sliding.A steeper base slope angle brings a larger range of damage.Strength parameters from back analysis by different slip surface are close, the average value is 33.2°, with standard deviation of 0.96°.They bring close factor s of safety, with an average value of 1.12 and standard deviation of 0.015, which demonstrate 10% to 14% safety reserve of the slopes after failure.Because stones used in the model test are dry and have uniform particle size, so the failure process get in the model test is different from previous studies, test results can only be applied to gravel waste dump site with low groundwater.