Research on rock burst proneness index based on energy evolution in rock

An effective rock burst proneness index is significant to evaluate the rock burst risk accurately. The rock burst occurring depends on the quantity of elastic energy and the rate of energy release. First, the relational expression between elastic energy density and stress in rock under uniaxial compression is constructed theoretically, which shows that the elastic energy density increases nonlinearly with stress before failure and then releases fast over the peak strength. Secondly, a new rock burst proneness index is defined and the index considers the quantity of elastic energy and the rate of energy release simultaneously. Finally, the effect of initial elastic modulus, homogeneity degree and Poisson's ratio on the index is investigated and the index increases with increasing value of initial elastic modulus and homogeneity degree, while it decreases as the value of Poisson's ratio increases.