断续节理岩体模型试验及强度分析研究  

Model Test and Strength Analysis Research on Intermittent Joint Rock Mass

作　　者：胡波[1,2] 张楠[3] 王思敬[4] 陈俊生[1] 

机构地区：[1]国网电力科学研究院,南京210003 [2]河海大学水利水电学院,南京210098 [3]南京铁道职业技术学院,南京210015 [4]中国科学院工程地质力学重点实验室,北京100029

出　　处：《地下空间与工程学报》2011年第4期657-665,共9页Chinese Journal of Underground Space and Engineering

基　　金：江苏省自然科学基金(BK2009479);交通部科技教育司资助项目(200531800019)

摘　　要：采用理论分析同模型试验相结合的方法对共面闭合断续节理岩体的直剪强度特性进行研究。理论分析方面,引入法向变形协调条件,推导了模型的直剪强度公式。模型试验发现,全应力应变曲线主要经历了线弹性增长、节理面错动、次生裂纹起裂稳态扩展、节理面贯通破坏和残余强度五个阶段;峰值和残余强度都随正应力的增大而增大,而变形特性随正应力的变化规律性不强;峰值强度随节理连通率的增大而减小,低连通率时强度下降速度慢;节理两边分布的试样的强度普遍高于节理在中间的。对比发现,理论计算结果与试验值吻合较好。The theoretical analysis and model test are integrated to study the strength behavior of rock mass containing coplanar close intermittent joints in direct shear.Through introducing deformation compatibility equation in normal direction,the direct shear strength formulation is deducted based on the Mohr-Coulomb theory.According to the complete stress strain curve obtained from model tests,there are five typical stages in the failure process,namely linear elastic increment,slippage of the joints,steady development of post-cracking,the coalescence failure of discontinuous joints and the residual strength.The peak and residual strength increase with the increase of normal stress.There is no function to describe the relationship between deformation property and normal stress.The peak strength decreases with the increase of the joint connectivity rate,and the drop velocity is slow at low connectivity rate.The distribution of the joints also has influence on the strength of the rock mass.The similar material model test shows that the strength of model with joints on edge is bigger than that of the model with joints in the middle.The theoretical calculated results coincide well with experimental results.

关 键 词：断续节理 强度机制 模型试验 破坏特征 影响因素分析 

分 类 号：TV223.1[水利工程—水工结构工程]