A 3D thermal cracking model for rockbased on the combined finite-discrete element method

A three-dimensional coupled thermomechanical model is proposed which can simulate crack initiation, propagation and coalescence, as well as the distribution of stress and temperature during thermal cracking. The model consists of two parts: The temperature distribution of the system is calculated according to the heat conduction equation, the thermal stress caused by temperature is applied to the system equation and a mechanical calculation considering cracking is performed. Three examples are given to verify the model regarding the problems of heat conduction, thermomechanical coupling and thermal cracking. This model has the potential to be applied to geothermal or oil exploitation and nuclear waste disposal.