Microscopic acoustic emission simulation and fracture mechanism of cemented tailings backfill based on moment tensor theory

As an artificial pillar, the cemented tailings backfill (CTB) is not destroyed in a short time. It is of great significance to understand the fracture mechanism of CTB for mine backfilling design. Based on laboratory tests and moment tensor theory, the micro-structure parameters of CTB are calibrated, the acoustic emission (AE) simulation method of CTB on micro-scale is established, and the temporal and spatial evolution process and mechanism of CTB fracture under uniaxial compression are studied. The results show that: 1) The fracture of CTB is mainly caused by sliding friction between particles based on the analysis of the relationship between the parameters of AE events. 2) In the process of CTB uniaxial compression simulation, the fracture types of AE sources can be divided into three types: explosion, shear and implosion. Explosion events are dominant in quantity and energy release, followed by shear events and implosion events. 3) The fracture type of AE sources is determined by the force acting on the particles determines the fracture mechanism instead of the ratio between the number of micro-tensile and micro-shear cracks. The research results can provide theoretical guidance for the stability control of CTB.