基于中主应力强度准则岩石损伤本构模型研究

Study on the Constitutive Model of Rock Damage Based on Intermediate Principal Stress Criterion

从探讨基于中主应力效应的新的岩石微元强度表示方法及其服从Weibull随机分布的特点出发,并引入损伤修正系数 ,基于岩石三轴应力应变试验曲线,建立了岩石损伤统计本构模型。在此基础上,重点研究了Weibull分布参数以及损伤修正系数对岩石损伤本构统计模型的影响,并结合岩石三轴应力应变试验曲线的特点,对岩石损伤本构统计本构模型进行了合理修正。与试验结果及前人研究结果比较,该模型可以更好地模拟岩石在低围压下应变软化的情况,具有广阔的应用前景。

By discussing the form of new rock micro-unit strength based on intermediate principal stress criterion, which satisfies Weibull random distribution, and introducing a damage correction factor q, a statistical constitutive model of rock damage was developed based on the stress-strain curve of tri-axial tests for rocks. Moreover, the effect of the parameters of Weibull distribution and the damage correction factor on the model was studied. The model was rectified according to the properties of tri-axial stress-strain test curve of rock. Compared with the existing research results, this model can better simulate the rock strain softening under low confining pressure. Therefore, this model has broad prospects for application.