安岳县镇子镇天台村6组蒋家湾滑坡特征、形成机制及稳定性分析

Analysis of Landslide Characteristics,Formation Mechanism and Stability in the Jiangjiawan,Tiantai Village of 6 Groups,Zhenzizhen town,Anyue County

本文在安岳县镇子镇天台村6组蒋家湾滑坡野外勘查成果基础上,结合样品试验数据,对该滑坡的特征、形成机制以及稳定性进行了综合评价。结果表明:蒋家湾滑坡为第四系残坡积土体沿与下伏侏罗系遂宁组紫红色泥岩、砂岩接触面向下滑动的小型牵引式土质滑坡。由于长期的降雨及地表水下渗,下渗地表水在滑面富集、运移,致使滑带土强度降低,不利于斜坡的稳定,同时受人类工程活动在滑坡体前缘形成了临空界面,使前缘降低斜坡抗滑力,后缘增加斜坡下滑力,最终发生了滑坡迹象。在天然工况下趋于稳定状态,地震工况下处于基本状态,在强降雨或持续降雨等不利条件作用下趋于欠稳定状态,暴雨工况下更易失稳。建议对蒋家湾滑坡采取“抗滑桩+既有排水沟硬化(局部为新挖排水沟)+裂缝充填”进行地质灾害工程治理。

In this paper,based on the field exploration results of Jiangjiawan landslide in the Tiantai Village of6 groups,Zhenzizhen town,Anyue County,combined with the sample test data,the characteristics,formation mechanism and stability of the landslide are comprehensively evaluated.The results show that the Jiangjiawan landslide is a small traction soil landslide in the contact direction of sliding of the quaternary residual slope soil mass along with the reddish mudstone and sandstone of the underlying Jurassic Suining formation.Because of long-term rainfall and surface water infiltration,infiltration of surface water in the sliding surface enrichment,migration,causes the decrease of strength of sliding zone,is not conducive to the stability of slope,and in landslide front formed the opening interface of human engineering activities,lower the front slope sliding resistance,increase trailing edge slope,landslide happened eventually sign.It tends to be stable of natural conditions,it tends to be basically stable of seismic conditions,and it tends to be unstable adverse conditions such as heavy rainfall or continuous rainfall,in particular of heavy rainfall conditions.We suggest that it beset up the"anti-slide pile+hardening of existing drainage ditch(new drainage ditch in partially)+fissure filling"for geological disaster engineering treatment of Jiangjiawan landslide.