Pressure relief, shock absorption, and energy absorption effects of protective layer mining

Protective layer mining represents one of the most effective and economical regional strategies for rock burst prevention.Studying its anti-impact mechanisms carries significant scientific implications and provides substantial guidance for engineering applications.This study systematically investigates the pressure relief, vibration damping, and energy absorption effects of protective layer mining by integrating theoretical analysis, numerical simulation, and engineering practice.The results demonstrate that, within a certain temporal and spatial range after protective layer extraction, both the stress and abutment pressure in the protected layer are markedly reduced, with a stress reduction rate reaching up to 25 %.Additionally, the frequency and intensity of dynamic loads induced by the fracture and slip of overlying strata are substantially attenuated.The loose and fragmented structures formed by protective layer mining effectively dampen far-field mining seismicity.Furthermore, following the prior extraction of the protective layer, the incremental strain energy near the working face during the mining of the protected layer is significantly decreased.The effectiveness of protective layer mining in mitigating rock burst hazards is closely related to factors such as interburden spacing, lithology of intervening strata, and coal seam thickness.Building upon these findings and contextualized within a developing mine, a design scheme for protective layer mining is proposed, laying a solid stress foundation for reducing the rock burst risk in the protected layer.reconstruction quality at a lower computational cost.The proposed method is further demonstrated to effectively bridge data gaps in incomplete time series, as illustrated using Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On gravity field solutions.