挤压带岩体特性及其对重力坝抗滑稳定性的影响  

Characteristics of Fractured Belt in Concrete Gravity Dam Foundation and It's Influence on the Stability against Sliding

作　　者：唐军峰[1] 杨军[1] 曾祥喜[1] 熊建平[1] 李学政[1] 

机构地区：[1]中国水电顾问集团中南勘测设计研究院,湖南长沙410014

出　　处：《资源环境与工程》2010年第5期441-445,共5页Resources Environment & Engineering

摘　　要：为分析坝基岩体挤压破碎带力学特性及其对重力坝抗滑稳定的影响,根据岩体微观测试、力学试验成果,建立了有限元数值模型,采用强度折减法研究了正常蓄水位条件下的坝体力学特性。研究结果表明,挤压带岩体结构松散,晶体结构以黏土矿物为主,具有很强的亲水性;饱和条件下,挤压带岩体抗剪强度大大低于非饱和条件下的强度;大坝蓄水后,坝基的潜在滑移模式表现为顺挤压带岩体的深层滑动,极限条件下的折减系数为2.37,小于规范要求,采用剪摩法计算时取值3.0。根据以上分析,建议重点对坝基挤压带岩体进行部分开挖置换和固结灌浆处理,同时做好防渗帷幕,降低水对挤压带岩体的弱化作用。In order to analyze the mechanical characteristics of fractured belt and its influence on the stability against concrete gravity dam sliding,micro structural test with mechanical experience was carried out,and the FEM model,based on strength reduction method was built to analyze the mechanical behavior of the dam while impounded.The results indicate that the fractured belt rock mass has loose structure,composed with clay mineral,and has strong hydrophilic nature.While in situation with saturation,the shear strength decreased rapidly compared with the non-saturation condition.After impounded,the analysis of anti-sliding stability in deep foundation was carried out,and the potential slipping plane along the fractured belt was found with factor of safety 2.37,less than the code required value,i.e.,3.0.Based on the analysis above,some advices were put forward,including excavate and represent with concrete for the fractured belt,consolidation grouting and anti-seepage curtain were also needed to reduce the effect of water to the fractured belt rock mass.

关 键 词：挤压带 重力坝抗滑稳定 岩体测试 强度折减法 

分 类 号：TV223[水利工程—水工结构工程] TV642.3