降雨渗流作用下贵州碎屑岩地区浅层滑坡形成机制分析  

Analysis of the formation mechanism of shallow landslides in the clastic rock area of Guizhou under the action of rainfall seepage

作　　者：王嵩 李军[1] 何旭东[1,2] 贺太红 WANG Song;LI Jun;HE Xu-dong;HE Tai-hong(114 Geological Brigade of Guizhou Geological and mineral exploration and development Bureau,Zunyi,563000,Guizhou,China;College of Resources and Environmental Engineering,Guizhou University,Guiyang 550025,China)

机构地区：[1]贵州省地质矿产勘查开发局114地质大队,贵州遵义563000 [2]贵州大学资源与环境工程学院,贵州贵阳550025

出　　处：《地下水》2024年第5期177-180,共4页Ground water

基　　金：赤水市地质灾害“隐患点+风险区”精细化调查评价(黔财资环[2023]87号);贵州省兴义市地质灾害详细调查及风险评价。

摘　　要：贵州省滑坡地质灾害多发育于碎屑岩区,降雨是主要诱发因素,研究碎屑岩区滑坡形成机制与降雨渗流的关系,对做好防灾减灾具有现实意义。本文以贵州兴义者央滑坡为例,在现场勘查和资料收集的基础上,分析了滑坡地质结构特征,构建了数值模型,通过叠加不同降雨强度和排水条件下的渗流分析结果,采用Fredlund双变量非饱和土抗剪强度理论和Janbu法计算滑坡稳定性系数,得到滑坡稳定性与降雨强度和排水条件之间的关系,揭示了降雨渗流作用下碎屑岩地区浅层滑坡的形成机制。研究显示:随着降雨强度的增加,滑坡的稳定性下降幅度增大、下降速率加快。同时,入渗雨水排泄受阻时,滑坡稳定性系数会进一步降低。研究结果可为同类滑坡的稳定性分析及治理提供参考依据。Landslide geological disasters in Guizhou Province are mostly developed in clastic rock areas,and rainfall is the main triggering factor.Studying the relationship between the formation mechanism of landslides in clastic rock areas and rainfall seepage is of practical significance for disaster prevention and reduction.This article takes the Zheyang landslide in Xingyi,Guizhou as an example.Based on on-site investigation and data collection,the geological structure characteristics of the landslide were analyzed,and a numerical model was constructed.By overlaying the seepage analysis results under different rainfall intensities and drainage conditions,the Fredlund bivariate unsaturated soil shear strength theory and Janbu method were used to calculate the landslide stability coefficient.The relationship between landslide stability and rainfall intensity and drainage conditions was obtained,revealing the formation mechanism of shallow landslides in clastic rock areas under rainfall seepage.Research shows that with the increase of rainfall intensity,the stability of landslides decreases more significantly and the rate of decline accelerates.At the same time,when the drainage of infiltrated rainwater is obstructed,the stability coefficient of the landslide will further decrease.The research results can provide reference for the stability analysis and treatment of similar landslides.

关 键 词：碎屑岩 浅层滑坡 降雨渗流 数值模拟 稳定性 

分 类 号：P642.22[天文地球—工程地质学]