On mechanisms for failures of some rock slopes in Rio de Janeiro, Brazil: thermal fatigue?

摘要

It has been observed along the years that a number of failures in rock slopes, more frequently in slopes of stone quarrying areas of Rio de Janeiro, occurred predominantly in relatively dry periods, corresponding to the months of June, July and August when little, if any, rain fell. The present paper describes these events and discusses possible mechanisms for their occurrence. It is believed that daily fluctuations in temperatures, especially during the winter (dry) months in Rio de Janeiro, may create thermally induced stresses of magnitude to propagate cracks already existing in the rock mass. A failure mechanism based on crack propagation in the rock mass under thermally induced stresses is proposed.