Numerical modelling of fracture processes in thermal shock weakened rock

This paper presents some preliminary results of a research project aiming at the simulation of thermal shock assisted percussive drilling. In the present study, a numerical model for transient thermal shock induced damage in rock is presented. This model includes a rock mesostructure description accounting for different mineral properties and a thermo-mechanical constitutive model based on embedded discontinuity finite elements. In the numerical simulations, the thermal shock induced damge process is first simulated. Then the uniaxial
compression test on thermally affected numerical rock samples is carried out. The effect of thermal shock is demonstrated by comparison to uniaxial compression test simulation on intact rock. The results show that the thermal-shock assisted rock breakage is a feasible idea to be extended to percussive drilling as well.