ABSTRACT
Accelerations exceeding that of free-fall indicate that the cave-in process is accompanied by release of elastic forces accumulated in the rock mass during changes in the stress distribution field. The poor understanding of the dynamic processes occurring in rock masses requires a new approach to their investigations since, under specific combinations of geomining factors, these processes may play a major role in failure of supports, coal pillars etc. Increase of stress in the seam before its failure may be explained by the appearance of inertial forces in the rock mass when they go into motion. The conditions which must accompany this phenomenon are violation of the system equilibrium and erratic nature of movement of the rock mass. Numerous analytical and experimental solutions have been developed for predicting the strength properties of rocks.
