Physics-based simulation of multiple interacting crack growth in brittle rocks driven by thermal cooling

Crack growth in hot brittle rocks, driven by thermal cooling, was simulated using a coupled two-dimensional discrete element and heat transport model that explicitly includes the random initiation and subsequent propagation of interacting cracks. The model clearly predicts that a quasi-hierarchical array of subparallel cracks, oriented along the direction of the temperature gradient, is formed under small to moderately large thermally generated strain load conditions. The simulation results also demonstrate that, after an initial transient, thermal cracks propagate in a stable fashion with a velocity that scales with similar to t(-1/2). However, under large thermal strain loads, a more complicated geometry composed of cracks that curve and coalesce develops during the later stages of crack growth. Copyright (c) 2016 John Wiley & Sons, Ltd.