Eancing Rock Mass Stability Through the Efficient Utilization of Backfill

Backfills have gained significant attention as sustainable materials for recycling waste generated in underground mining processes. However, a comprehensive understanding of the efficient mechanisms and their effects on underground rock mass stability under varying conditions is still necessary. This paper investigates the failure process of two different rock-backfill structures through triaxial compressive experiments, employing acoustic emission (AE) and computed tomography (CT) technology. The study reveals the cooperative behavior of the bi-material system and identifies four key reactions of the backfills on the rock mass: stress redistribution, energy absorption, intact force, and intact friction. The specific reactions and their sensitivities depend on the structure and external confinement applied to the system. Considering the volume fraction of the materials and the external loading, the study presents technical recommendations for utilizing backfills in diverse mining conditions. These findings provide insights for more efficient and flexible design considerations when implementing the backfilling mining method, contributing to a greener and sustainable future.