[关键词]
[摘要]
采用极限平衡理论,对南水北调中线工程膨胀土-换填土渠坡,在降雨渗流及堤顶超载影响下的失稳模式进行计算研究及超载试验研究,得到了渠坡的最危险失稳模式及其失稳破坏状态。结果表明:1)最危险渠坡滑裂面是位于膨胀土渠坡浅表范围内含有块间破裂面的复合曲面或单一曲面。2)堤顶超载对渠坡稳定有显著不利影响,极限堤顶超载值约为0.44倍渠坡高度的土柱荷重或1.4倍汽-20加重车均布荷重。该结果可为工程合理设计及安全施工、运行提供有益的参考。
[Key word]
[Abstract]
Unstable modes of expansive and replacement soil slope under the impacts of rainfall seepage and overload in the Middle Route of South-to-North Water Diversion Project were investigated using the limit equilibrium theory. The most dangerous instability mode and state of unstable destruction were obtained. The results showed that (1) the most dangerous sliding surface is the single curved surface or compound curved surface which has rupture surface between blocks in the shallow layer of expansive soil slope; and (2) the overload of slope top has significantly adverse impacts on slope stability. The limit overload value of of slope top is about 0.44 times of the weight of the soil column with the slope height or 1.4 times of the weight of the uniformly distributed load produced by the car with a carrying capacity of 20 tons. The results can provide beneficial reference for the reasonable design and safe construction and operation of the project.
[中图分类号]
[基金项目]
南水北调工程科技项目:南水北调中线一期工程总干渠河北段膨胀土工程特性研究