Evolution of Both Stress and Energy Fields in MRADS After Pressure Relief by Waterjet

Abstract

Studying on the evolution and mechanism of rock bursts is aimed at preventing them from bursting so as to ensure safety production, and understanding the spatiotemporal evolution properties of stress, energy, and other characteristic parameters in the RADS is aimed at seeking reasonable means to weaken the degrees of both stress concentration and energy accumulation for disaster prevention. In essence, the prevention and control of rock bursts are to affect energy dissipation and stress transfer by changing the mechanical properties of coal rock mass and the external surrounding rock conditions in the RADS. Waterjet with coal rock disintegrating and softening functions can damage the internal structure of coal rock mass and effectively dissipate energy and change the external stress state. Therefore, it is significant examining the development and variation of coal rock mass in the RADS under the action of waterjet pressure relief. This chapter mainly discusses the mechanism of rock disintegration with waterjet underlined, analyzes the coalbed pressure relief method and energy dissipation behaviors based on waterjet, and preliminarily investigates the waterjet rock-fracturing effect through physical similarity experiment and, based on which, numerically simulates the evolutional characteristics of both stress and energy fields in the MRADS under the pressure relief conditions.