THERMAL FAILURE BEHAVIOR OF ROCK AT HIGH TEMPERATURES

Laboratory heating experiments were conducted to investigate the behavior of rocks under thermal stress. The experimental results indicated that the thermal failure behavior of rock greatly depended on rock types and confining conditions. Thermal stress analysis by the finite element method was carried out using the rock properties obtained from laboratory tests at high temperatures. The comparison between the results of this analysis and those of the experiments elucidated that it was essential in the analysis to consider the temperature dependence of rock properties, the thermal expansions in particular. This consideration allows the prediction of the location and time of fracture initiation caused by thermal stress.