库水条件下滑坡体与挡墙相互作用研究

Study of interaction of landslide mass and retaining wall under condition of reservoir water

基于鹤峰乡场镇滑坡地质模型,利用有限差分法FLAC3D分析库水作用下滑坡体和挡墙结构的相互作用,得到了较好的数值模拟结果。研究结果表明:①挡墙墙踵处产生局部拉应力;②剪应变增量沿挡墙和基岩的"薄弱接触面"由墙背向墙面推移式发展(即呈">"发展模式);③滑坡体和挡墙有共同的变形趋势,上部变形大,下部较小,位移等值线相互平行以及浅层滑坡对挡墙造成"层状破坏";④滑坡发生浅层滑移,滑坡和挡墙的稳定性降低。提出以位移指标评价库水条件下挡墙的抗滑稳定性和抗倾覆稳定性,并确定挡墙的临界宽度,在此基础上对挡墙结构进行优化设计,提高滑体和挡墙的稳定性,其结果为地质灾害的防治和工程设计提供理论指导。

Basing on geological model of Hefeng landslide and using finite difference method to analyze the interaction of landside mass and retaining wall under condition of reservoir water,we can get satisfying results.Under the condition of reservoir water,the results show： ①Local tensile stress appears in the wall heel of retaining wall;②The increment of shearing strain process developed（＂＂development mode） from backwall to metope along retaining wall and ＂weak contact face＂ in stone head;③The landside mass and retaining wall have same deformation tendency,and the upper deformation is larger than the under-part;The isolines of displacement are parallel to each other,and the retaining wall is bedded destroyed because of shallow landslide;④The landslide is shallow slippage,and the stability of landside and retaining wall go down.In the end,the paper points out that drift index can be used to evaluate anti-slide stability and anti-tipping stability and determine critical width of retaining wall under the conditions of reservoir water;and then the stability of landslide and retaining wall can be improved for the optimization design of retaining wall.All of these will provide theoretical guiding for geologic hazard control and engineering design.