岩石化学腐蚀-围压损伤本构模型与离散元模拟研究  

Chemical Corrosion-confining Pressure Damage Constitutive Model and Discrete Element Simulation of Rock

作　　者：陈有亮[1,2] 陈奇键 肖鹏 杜曦 王苏然[4] Youliang Chen;Qijian Chen;Peng Xiao;Xi Du;Suran Wang(School of Environment and Architecture,University of Shanghai for Science and Technology,Shanghai,200093;Department of Engineering Geology and Hydrogeology,RWTH Aachen University,Aachen,52064,Germany;School of Civil and Environmental Engineering,University of New South Wales,Sydney,2052,Australia;Department of Underground Architecture and Engineering,Tongji University,Shanghai,200093)

机构地区：[1]上海理工大学环境与建筑学院,上海200093 [2]亚琛工业大学工程地质与水文地质系,德国亚琛52064 [3]新南威尔士大学土木与环境工程学院,澳大利亚悉尼2052 [4]同济大学地下建筑与工程系,上海200093

出　　处：《固体力学学报》2022年第6期703-715,共13页Chinese Journal of Solid Mechanics

基　　金：国家自然科学基金项目(10872133);上海市软科学研究领域重点项目(18692106100)资助。

摘　　要：基于Lemaitre应变等价性假设理论,假定受水化学-力耦合损伤的岩石微元强度服从Weibull分布,考虑化学腐蚀与围压耦合作用对岩石力学参数的影响,通过核磁共振技术与损伤力学理论,引入化学损伤变量与力损伤变量,并认为微元破坏符合SMP准则,建立岩石化学腐蚀-力耦合损伤本构模型,并采用理论推导的方法得出所需的模型参数.同时基于颗粒离散元方法,引入参数半径乘子来改变颗粒间的黏结接触尺寸,从而模拟水化学损伤,采用平直节理模型对水化学作用后的岩石进行三轴压缩模拟,得到了水化学作用和不同围压下的岩石三轴应力-应变模拟曲线.通过对比所构建的岩石化学腐蚀-力耦合损伤本构模型理论曲线、离散元模拟曲线和试验曲线,结果表明三者吻合度较好,能够很好地反映岩石在化学腐蚀和围压耦合作用下的力学特性与破坏特征,并通过离散元方法得到了岩石在三轴压缩过程中裂纹的产生与分布情况.Based on Lemaitre’s theory of strain equivalence hypothesis,the coupling effect of chemical corrosion and confining pressure on mechanical parameters of rock was considered.Through nuclear magnetic resonance technology and damage mechanics theory,the chemical damage variables and force damage variables were introduced,and the micro-element damage conformed to the SMP criterion.The evolution equation and constitutive model of the chemical corrosion-mechanics coupling damage of rock were established,and the required model parameters were obtained by theoretical derivation.Based on the particle discrete element method,the parameter radius multiplier was introduced to change the size of the bonding contact between particles,so as to simulate the hydrochemical damage.The flat-joint model was used to simulate the triaxial compression of the rock after hydrochemical action,and the triaxial simulation curves of the rock under hydrochemical action and different confining pressures were obtained.The theoretical curve,the test curve,and the discrete element simulation curve of the constructed chemical corrosion-mechanical coupling damage constitutive model of rock showed good agreement.The generation and distribution of cracks in rock during triaxial compression were obtained using the discrete element method.

关 键 词：水化学损伤 本构模型 SMP准则 PFC模拟 平直节理模型 半径乘子 

分 类 号：TU45[建筑科学—岩土工程]