单轴拉伸条件下细观非均匀性岩石本构关系研究  

A STUDY ON THE COMPLETE STRESS-STRAIN RELATION FOR MESOSCOPIC HETEROGENOUS ROCKS UNDER UNIAXIAL TENSILE LOADING

作　　者：周小平[1] 张永兴[1] 朱可善[1] 

机构地区：[1]重庆大学土木工程学院

出　　处：《土木工程学报》2005年第3期87-93,共7页China Civil Engineering Journal

基　　金：国家自然基金资助项目 (598790 1 2 ;596490 0 8)

摘　　要：用损伤力学理论研究了细观非均匀性岩石拉伸应力应变关系(包括线弹性阶段、非线性强化阶段、应力降阶段、应变软化阶段) ,分析了产生应力跌落和应变软化的主要原因是损伤和变形局部化,将损伤和变形局部化引入本构模型是和以往模型的重要区别。通过和试验成果对比分析验证了模型的正确性和有效性。Stress redistribution induced by excavation often resul ts in tensile zones in the surrounding rock mass.It is of great theoretical and pr actical significances to analyse the localizations of deformation and damage an d to study the complete stress-strain relation for mesoscopic heterogenous rock s under uniaxial tensile loading.Based on damage mechanics,the complete stress- strain relation,including linear elasticity,non-linear hardening,rapid stress d rop and strain softening,is obtained.The rapid stress drop and strain softening are due to localizations of deformation and damage.The constitutive model,which analyzes the localizations of deformation and damage,is distinct from the conven tional model.Theoretical predictions have shown consistency with the experimenta l results.

关 键 词：单轴拉伸 细观非均匀性岩石 损伤力学 损伤和变形局部化 应力应变全过程 

分 类 号：TU454[建筑科学—岩土工程]