降雨入渗作用下秭归向斜核部南段斜坡稳定性评价  

Slope Stability Evaluation of Southern Section of Zigui Syncline Core Under Rainfall Infiltration

作　　者：齐信[1] 刘广宁[1] 黄波林[1] 王世昌[1] 黄长生[1] 

机构地区：[1]中国地质调查局武汉地质调查中心,湖北武汉430205

出　　处：《水土保持通报》2017年第3期97-101,共5页Bulletin of Soil and Water Conservation

基　　金：国家自然科学基金项目"基于水波动力学的水库崩塌滑坡涌浪研究"(41372321);中国地质调查局灾害预警项目(12120114079301);水工环调查项目(DD20160257)

摘　　要：[目的]开展降雨条件下湖北省秭归县向斜核部斜坡稳定性评价研究,为政府部门减灾防灾工程提供科学支持,为滑坡灾害的预测和管理提供科学依据。[方法]以耦合了地下水动力学的TRIGRS无限斜坡稳定性计算模型为基础,详细介绍了斜坡稳定性评价的数据处理过程以及参数选取方法。[结果]发生斜坡失稳的区域多位于松散土体中等厚—较厚,地形坡度中等的区域,尤其是土层厚度在7—10m,地形坡度在20°~30°范围内为斜坡失稳高发区。[结论]在土层厚度和地形地貌的双重控制下,短历时强降雨入渗作用导致孔隙水压力增大,这些区域的斜坡土体极易发生滑动,为滑坡危险性较高的多发区域。斜坡稳定性评价结果和滑坡实际分布吻合程度较高,在一定程度上反映出降雨诱发滑坡空间分布关系和分布规律。[Objective] The main stream of synclinal basin core in Zigui County of Hubei Province was selected as an case study area, and the slope stability evaluation under transient rainfall infiltration was carried out to provided scientific support for disaster prevention and mitigation projects of government departments, and to provide scientific basis for landslide hazard prediction and management.[Methods] Based on TRIGRS infinite slope stability calculation model coupled with groundwater dynamics, the data processing procedure and parameter selection methods of the slope stability evaluation tool was introduced in detail.[Results] Slope instability mainly located in the region with loose soil having medium thick or thicker layer, and medium slope, especially in the region having soil thickness of 7 to 10 m, and terrain slope ranged 20° to 30°, where were high incidence areas of slope instability.[Conclusion] Under the synergic effects of soil layer thickness and topography, short-duration but heavy rainfall can lead to the increase of pore-water pressure, where slope sliding happen easily, which was determined as landslide high risk area. The slope stability evaluation results were in good agreement with the actual distribution of landslides, and it can reflect the spatial distribution of rainfall-induced landslides to some extent.

关 键 词：TRIGRS模型 斜坡稳定性评价 瞬态渗透模型 秭归向斜盆地 

分 类 号：P642.22[天文地球—工程地质学]