基于最小耗能原理的岩石损伤本构模型研究  

Study on damage constitutive model of rock based on principle of minimum dissipative energy

作　　者：孙梦成 徐卫亚[1,2] 王苏生 王如宾[1,2] 王伟[1,2] SUN Mengcheng;XU Weiya;WANG Susheng;WANG Rubin;WANG Wei(Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering,Hohai University,Nanjing 210098,China;Institute of Geotechnical Engineering,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,江苏南京210098 [2]河海大学岩土工程科学研究所,江苏南京210098

出　　处：《中南大学学报（自然科学版）》2018年第8期2067-2075,共9页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51479049;51679069);江苏省研究生科研与实践创新计划项目(KYCX17_0471;2017B700X14)~~

摘　　要：在连续损伤理论框架下引入最小耗能原理,将岩石统一能量屈服准则作为耗能约束条件,基于各向同性基本假定构建一种新型损伤本构模型。假定以岩石初始屈服点作为损伤阈值,模型考虑损伤阈值对损伤演化规律的影响;推导岩石三轴压缩强度和变形参量与模型参数的理论关系。为验证模型的合理性,对角砾熔岩进行不同围压下的常规三轴压缩试验,并分析破坏过程中岩石变形各阶段的能量演化特征。研究结果表明:该模型能较好地反映岩石材料在复杂应力条件下的非线性力学行为,且考虑损伤阈值影响的模型对岩石后屈服段的拟合精度更高,对复杂应力条件下的岩石工程安全分析具有参考价值。The principle of minimum dissipative energy was introduced based on the continuum damage theory.Taking unified energy yield criterion of rock as the constraints of energy dissipation,a new damage constitutive model was proposed based on the assumption of isotropy.The new damage constitutive model took into account the influence of damage threshold which was assumed to be the starting point of initial yield phase.Furthermore,the theoretical correlation between model parameter and deformation moduli of rock under triaxial compression was deduced.A series of conventional triaxial tests on breccia lava samples were carried out under different confining pressures,and evolution characteristics of energy at different stages of rock deformation and failure were analyzed to verify the rationality of model.The results show that the model can not only reflect the nonlinear mechanical characteristics of rock materials under complicated stress condition,but also has high fitting precision on post-yield stage of rock,which can provide reference for safety analysis of rock engineering under complicated stress condition.

关 键 词：岩石力学 最小耗能原理 岩石统一能量屈服准则 损伤阈值 损伤演化方程 

分 类 号：TU452[建筑科学—岩土工程]