强降雨诱发茅台镇某滑坡复活变形机理及稳定性研究  

Study on the Deformation Mechanism and Stability of a Landslide Resurrection Induced by Heavy Rainfall in Maotai Town

作　　者：阮凡 何旭东[1] 唐文佳 陈佳斌 RUAN Fan;HE Xudong;TANG Wenjia;CHEN Jiabin(114 Geological Brigade,Guizhou Geological and Mineral Exploration and Development Bureau,Zunyi 563000,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

出　　处：《河南科技》2023年第4期111-114,共4页Henan Science and Technology

摘　　要：【目的】强降雨作用是诱发滑坡变形及古滑坡复活等地质灾害的主要因素之一。通过研究强降雨条件下滑坡失稳变形机理及特征对开展滑坡灾害气象预警及监测意义重大。【方法】以贵州省仁怀市茅台镇仁文村海椒坪大型古滑坡为例,基于现场勘测的多源数据融合及室内试验成果,深入分析强降雨作用下该滑坡的复活变形演化规律。【结果】滑坡区较大的汇水面积及降雨持时过长,导致水沿中后缘滑塌区拉裂缝和右侧缘倾向节理与老崩滑堆积体接触带向下渗透。高含水率导致岩土体强度参数劣化,其中内摩擦角对坡体稳定性的影响系数是黏聚力的5~7倍。粉质黏土的过饱及富水环境为动水压力触发滑坡启动创造了条件,中后缘次级剪出部分已处于欠稳定状态,在短期强降雨条件下极易发生整体滑动并形成堰塞湖。【结论】可为该类滑坡的气象预警与防治提供参考。[Purposes] The effect of heavy rainfall is one of the main factors inducing geological hazards such as landslide deformation and paleolandslide resurrection.By studying the mechanism and characteristics of landslide destabilization and deformation under heavy rainfall conditions,it is significant to carry out weather warning and monitoring of landslide disasters.[Methods] Taking the large ancient landslide of Haijiao Ping in Renwen Village,Maotai Town,Renhuai City,Guizhou Province as an example,the resurgence deformation evolution law of the landslide under the effect of heavy rainfall was analyzed in depth based on the fusion of multi-source data from field survey and indoor test results.[Findings]That the large water catchment area of the landslide area and the long rainfall holding time lead to the downward infiltration of water along the middle and rear edge of the landslide area pulling cracks and the right edge tendency joints and the contact zone of the old avalanche-slide accumulation.The high water content leads to the deterioration of the strength parameters of the geotechnical body,in which the coefficient of influence of the angle of internal friction on the stability of the slope is 5~7 times higher than that of the cohesive force.The over-saturated and water-rich environment of the powder clay creates conditions for the dynamic water pressure to trigger landslide initiation,and the secondary shear-out part of the middle and trailing edge is already in an unstable state,which is highly susceptible to overall sliding and formation of a weir under short-term heavy rainfall conditions.[Conclusions] The results of the study can provide a reference for the meteorological warning and prevention of this type of landslide.

关 键 词：强降雨 入渗机制 滑坡变形 稳定性 

分 类 号：P642.22[天文地球—工程地质学]