Subcritical crack propagation in westerly granite: An investigation into the double torsion method

This study considers the effects of cyclic differential heating on the velocity of the subcritical crack growth (SCG) from a central notch in rock beams under four-point bending test. Beams of both Carrara marble and Fujian granite are subjected to non-uniform heating, with heating from the top surface containing the notch (at about 60° Celsius) and with cooling to the bottom side with no notch (at about 25° Celsius). Beams are heated for 7–188...