岩土类材料率相关性及硬化-软化特性模型研究  

Study of rate-dependence and hardening-softening characteristics of rock and soil material

作　　者：王小平[1] 夏雄[1] 

机构地区：[1]常州大学岩土工程研究所,江苏常州213164

出　　处：《岩土力学》2011年第11期3283-3287,共5页Rock and Soil Mechanics

摘　　要：岩土类材料具有显著的率相关性,其应力-应变关系全过程一般表现为硬化-软化特征,研究如何描述这两类特征具有重要的意义。基于岩土类材料的物理变形机制分析,考虑到其结构性特征,采用弹黏塑性本构模型,引入反映材料结构变化的可变结构黏滞系数及其演化方程,并将其嵌入到弹黏塑性本构模型中去,建立能够反映材料结构变化的弹黏塑性本构模型。利用玄武岩常规三轴常应变率试验结果对所建立的模型进行试验验证,结果表明:所建立的弹黏塑本构模型能够完整、合理地描述岩土类材料应力-应变关系全过程以及材料本构关系的率相关性,同时还能够反映材料的峰值强度、残余强度特征。Rock and soil material has strong rate dependence;its complete stress-strain relation belongs to the type of hardening-softening,It is important to describe these two characteristics.Based on the analysis of physical deformation mechanism,considering the structure characteristic,the elasto-viscoplastic model is used.To set up the elasto-viscoplastic model which can describe the structure changes,the variable viscosity coefficients and its evolution equation are applied to the elasto-viscoplastic model.The result of basalt normal triaxial constant rate test is used to test the rationality of the model.The result shows that the model can completely and rationally describe the complete stress-strain relation and its rate dependence,and also the peak strength,residual strength characteristic.

关 键 词：率相关性 硬化-软化 结构黏滞系数 弹黏塑性模型 常应变率试验 

分 类 号：O345[理学—固体力学]