基于中主应力的岩石统计损伤软化模型参数研究

岩石本构关系问题一直是岩石力学研究的重点问题,基于损伤力学理论,假设岩石的损伤变量分别服从幂函数分布与正态分布,建立考虑中主应力影响的模型,总结参数规律。通过两种分布函数所建立的岩石统计损伤软化本构模型与试验结果对比,以及分析损伤变量D的数值变化探讨模型适用性,研究表明:建立的模型曲线均能够较为理想地与实验曲线吻合,与岩石材料的力学性质基本吻合。而正态分布函数模型较幂函数分布模型的损伤变量D演化趋势更为合理。

Study on the Parameters of Statistical Damage Constitutive softening Models of Rock Based on SMP criterion

Constitutive relation of rock has been the focus of the rock mechanics. Assuming that the rock damage variable follows a power function distribution and normal distribution, respectively, based on damage mechanics theory, a rock statistical damage softening constitutive model is established based on SMP criterion, then the parameters of two kinds of the models were studied by using several calculation methods. Through comparing the result of two models with the experimental results and analyzing the changes of damage variable value D to explore models’ applicability, it is shown: the predicted stress-strain curves under different confining pressures agree well with the test data, models are able to reflect the property of the peak strength increases and ductility increases with the confining pressure increase, and the changes of damage variable D of the normal function model is more reasonable.