MODELLING OF THERMAL CRACKING PROCESS OF ROCK BASED ON COUPLED THERMO-MECHANICAL-DAMAGE MODEL

摘要

In this paper, a numerical method, RFPA-thermal code with a coupled thermo-mechanical-damage constitutive model for rock in the framework of continua mechanics, is applied. The evolution of damage is motivated by thermal stress. In the model, three components, viz., a heat flow description, a stress description, and a failure description, are respectively considered to describe the coupled heat transfer and rock failure problems associated with thermal cracking. Examples are presented in the paper illustrating how the overall macroscopic thermal response of rock materials can be simulated by integration of the interactions between smaller-scale elements. The deformation and failure process of rock induced by thermal cracking was simulated and investigated to gain an insight into the mechanism of the complex thermal cracking between heat flow and rock deformation. The simulated thermal cracking characteristics of the rock greatly helped in the interpretation of the experimental results and the observed phenomena in fields.