渌吝水库左坝肩边坡滑坡原因分析  

Analysis of causes for slope landslide on left abutment of Lulin Reservoir

作　　者：陈涛[1] CHEN Tao(Guangxi Water&Power Design Institute Co.,Ltd.,Nanning 530023,China)

机构地区：[1]广西水利电力勘测设计研究院有限责任公司,南宁530023

出　　处：《广西水利水电》2023年第4期17-22,共6页Guangxi Water Resources & Hydropower Engineering

摘　　要：渌吝水库工程由于地质条件复杂且变化大,开挖过程中坝轴线上游边坡发育有泥岩条带软弱夹层,倾角倾向下游,与左岸发育的J1、J2两组节理裂隙组合形成不利结构面,加上强降雨,老滑坡体覆盖层及软弱层上部基岩吸水后重度增大,地下水下渗后沿软弱层渗出,产生顺坡向的渗流压力,降低老滑坡体覆盖层及软弱夹层、节理裂隙的抗剪强度,导致滑坡产生。利用赤平投影边坡稳定性分析得出该滑坡现状整体稳定性差,雨季易再次发生坍塌、滑坡等不良地质作用,建议采用削坡减载措施,同时需做好边坡的排水及防水措施,并对坡面进行防护,防止暴雨冲刷、避免雨水下渗软化边坡岩土体。The geological conditions of Lulin Reservoir Project are complex.In the course of excavation,developed mudstone strip weak interlayer was found on the slope upstream of the dam axis,dipping into downstream and constituting adverse structural plane combined with the joint fissures J1 and J2 developed on the left bank.Intense rainfall led to increase of the weight of overburden of old landslide mass and base rock above the weak interlayer after absorbing water.Groundwater seeps down along the weak layer,generating seepage pressure along the slope,which lowered the shear strength of the overburden of old landslide mass,the weak interlayer and the joint fissures,and finally led to the landslide.The results of slope stability analysis conducted by stereographic projection method demonstrate this landslide mass has poor overall stability and is liable to slide again in rain season.It is suggested to cut the slope and reduce the load,improve the drainage and waterproofing of slope,protect the slope surface from rain scouring and avoid rainwater seeping down and softening the slope rock or earth mass.

关 键 词：软弱夹层 节理裂隙 边坡稳定 地质处理 渌吝水库 

分 类 号：P642.22[天文地球—工程地质学]