中低围压下细观非均匀性岩石本构关系研究

Study on the complete stress-strain relation for mesoscopic heterogenous rock under triaxial compression with moderate or low lateral compressive stress

研究了中低围压条件下细观非均匀性岩石的变形局部化问题和全过程应力应变关系。研究表明,全过程应力应变关系包括线弹性阶段、非线性强化阶段和应变软化阶段。分析了产生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本构模型的重要区别。通过和实验对比分析验证了模型的正确性和有效性。

Based on the selfsimilar model of microcrack growth,the localization of strain and damage,and complete stressstrain relation for mesoscopic heterogenous rock under triaxial compression with moderate or low lateral compressive stress are investigated.It is showed that the complete stressstrain relation includes the stages of linear elasticity,nonlinear hardening,and strain softening. The behaviour of strain softening is due to localization of deformation and damage.The constitutive model,which analyse localization of strain and damage,is distinct from the conventional model. Theoretical predictions have shown to be consistent with the experimental results .