大型砾岩滑坡特征与成因机制分析

Analysis on Characteristics and Genesis Mechanism of a Large-scale Conglomerate Landslide

为确定砾岩滑坡产生的成因机制,以国内西北地区大型砾岩滑坡为例,在调查滑坡体所处地质环境的基础上,查明了该滑坡的基本特征,结果表明:在有利的地形临空、砾岩岩性、地质构造、卸荷裂隙发育等条件下,遭受超常降雨作用,沿不利结构面发生滑移、后缘坡体逐渐拉裂,滑面最终贯通形成滑坡,本次砾岩滑坡的成因机制为滑移-拉裂型,滑动形式属于推移式。

In order to determine the genesis mechanism of conglomerate landslide,a large conglomerate landslide in northwest China is taken as an example,on the basis of investigating the geological environment of the landslide,the basic characteristics of the landslide are identified and the result shows:under the condition of favorable terrain,conglomerate lithology,geological structure,development of unloading fissures,etc.,the conglomerate mass suffers from abnormal rainfall,slips along the unfavorable structural surface which causes the gradual ripping of trailing edge,and finally the slip plane is cut through to form a landslide.The genesis mechanism of this conglomerate landslide is slipping-pulling type,and the sliding type is thrust load-caused landslide.