Dislocation migration analysis of blast-induced block instability in mining

This paper quantifies damage to the rock mass resulting from cyclic loading occurring as a result of blasting. The incurred damage is related to the fatigue of the rock mass and the fatigue life of the rock block is estimated. Results of this study permit determination of the probability of rock failure during the predicted life span of the mine. Damage is studied through the analysis of crack initiation and propagation according to the theory of dislocations. Following the crack initiation at microscopic scale, a macroscopic scale cumulative damage (crack propagation) results leading to local failure of the blocks existing within the rock mass. This paper presents the first part of the related study. It defines the monotonic part of blast cyclic loading of the rock block. The unloading part of the cycle will be presented in another paper.