STATISTICAL CONSTITUTIVE MODEL FOR ROCK DAMAGE BASED ON MOHR-COULOMB CRITERION

The process of rock failure can be much reflected by an appropriate constitutive model with damage variables.Based on rock micro-unit strength,the theoretical equations of damage variables evolution and statistical constitutive model for rock damage are established with Mohr-Coulomb damage criterion as distribution variable.Meanwhile,tri-axis constructive model is established,and parameters in the model can be calculated with arbitrary Tri-axis experimental data by using curve fitting and extreme value methods.So it is easy for engineering applications.The model is verified by experiments and agrees well with each other.The investigation shows rock strain characteristics under loads and the constructive relation between strain and stress of rock materials can be well reflected by the constructive model with damage variable based on Mohr-Coulomb damage principle as distribution variable.The model would be easily applied in practices.