A thermodynamic constitutive model for creep behavior of rocks and its application

作者：You Shuang; Zhang Zhichao; Ji Hongguang^*

来源：Journal of China University of Mining & Technology, 2016, 45(3): 507-513.

• Constitutive relations
• Creep failure
• Elastoplastic constitutive model
• High confining pressure
• Low confining pressure
• Non equilibrium thermodynamics
• Rock creep
• Visco-elastic behaviors

In this paper, a visco-elasto-plastic constitutive model was established based on non-equilibrium thermodynamics to analyze the creep behavior of rocks. Different from the classical elasto-plastic model, the visco-elasto-plastic constitutive relations in this model were derived from the perspective of energy storage, energy dissipation and energy fluctuation, and no concepts such as yield surface and flow rule were needed. The visco-elastic behavior was described by dividing the stress into the elastic stress and the viscous stress, while the visco-plastic behavior was described by the concepts of fluctuation and dissipative flow. Simulation results show that this model is capable of capturing the ductile failure of rocks under high confining pressure and the brittle failure under low confining pressure. Meanwhile, it is useful for the prediction and mechanism interpretation of the creep deformation and creep failure of rocks.

• 出版日期2016
• 单位清华大学