三峡库区千将坪滑坡地质特征与成因机制分析  

Characteristics and mechanism of Qianjiangping Landslide in Three Gorges Reservoir Area

作　　者：李会中 王团乐 孙立华[2] 段伟锋 

机构地区：[1]长江水利委员会三峡勘测研究院,宜昌443003 [2]天津市地质工程勘察院,天津300191

出　　处：《岩土力学》2006年第S2期1239-1244,共6页Rock and Soil Mechanics

基　　金：水利部科技创新项目(SCX2003-21)资助课题

摘　　要：秭归县千将坪滑坡是三峡水库蓄水至135 m 不久发生的中上部顺层、下部微切层巨型基岩滑坡,总方量约2 040×10~4m^3。据实地调查资料,阐述了滑坡地质背景与滑坡地质特征,分析了滑坡成因与力学机制。千将坪滑坡的发生是其独特内外因共同作用的结果,坡体三面临空、顺向坡地质结构、岩性软硬相间、岩层产状上陡下缓、棋盘格式的裂隙网络、不良的地表排水条件等为内因;持续的强降雨、三峡水库水位缓慢抬升、坡体后缘泉水的长期入渗则是其外部诱因,其中三峡水库水位的抬升与持续的强降雨则是其触发因素;坡体早期变形反映、"靠背椅状"顺向坡地质结构及高速滑动均说明滑坡滑动的源动力来自"高位能";千将坪滑坡具有"推落式滑坡"的力学特征。千将坪滑坡地质特征、成因与机制分析的调查研究对工程建设中类似斜坡的勘察以及类似滑坡的预测都具有重要借鉴价值。The Qianjiangping Landslide with total volume of 20,400,000m^3,occurred shortly after the water level raised to EL.135m after the impoundment of the Three Gorges Reservoir.This paper present the details of the geological settings and the geological characteristics of the landslide;meanwhile the 'mechanism of the sliding was analyzed.The dip slope structure,the harder strata interbedded with soft strata,the upper steep dipping beddings and the lower gentle dipping bedding provided the basic cause for the sliding.The continuous heavy rainfall and the toe of the slope submerging groundwater played important roles for sliding;especially the impoundment of the reservoir.The movement type and the high speed of the sliding and the'chair'shape slip face,showed the slope with high potential energy.This energy formed the unique'thrust'failure type.The Characteristics and the mechanism of the landslide can be adopted as the model for study and predicting the sliding for the similar type slope.

关 键 词：三峡库区 基岩滑坡 地质特征 成因机制分析 

分 类 号：P642.22[天文地球—工程地质学]