关键词: 花岗岩类边坡; 地质灾害; 变形破坏机理; 宏观判据;

Abstract: In order to find out the types and developmental distribution characteristics of granite slopes in the upper reaches of Xijiang River,and research the deformation failure mechanism and macroscopic criteria,based on the 1:50 000 survey,we obtained the data of geohazards investigation for granite slope.The type and the instability mode were divided and the mechanism of deformation and failure was analyzed,so as to provide macro criteria for early identification of geohazards in granite slopes.A total of 87 geohazards were investigated in the study area,all of them were small.The vast majority of the geohazards were completely and slightly-weathered,most of them were distributed in the slope area of 50～220 m and 25～45 degrees.The weathering degree played a dominated role in the deformation and failure mode,and it can be divided into 3 types:slip(slump),dump,and collapse(fall).Five factors such as weathering degree,slope type,terrain slope,joint fracture development and macroscopic deformation can be used as macroscopic criteria in the study of deformation and failure mode of granite slope in the region.The geohazards in the study area included the three deformation and failure mechanisms of "softening disintegration,progressive destruction and rigid failure".The mechanism of progressive deformation was reflected in all granite geohazards,the mechanism of softening and disintegration was mainly reflected in the moderately and completely-weathered granite,the mechanism of rigid deformation and failure was mainly reflected in the slightly-weathered and spherical-weathered granite slopes.

Key words: granite slope; geohazards; deformation and failure mechanism; macroscopic criteria;