Instability Hazard Effect of Mined-out Areas Near the Mining Site by Fusion InSAR and PSO-BP Rock Mechanical Parameter Inversion

Exploring the impact characteristics of near the mining activities on goaf and clarifying the disaster effects of instability in the mined-out area are critical research endeavors essential for effectively managing major risk hazards inherent to underground mining operations. This study integrates SBAS-InSAR and PSO-BP methodologies for inversely analyzing rock mechanical parameters in a lead-zinc deposit and applies the inversion results through the FLAC3D simulation method to the mining site adjacent to the null zone to study destabilizing disaster effects in the mined-out area under the influence of mining disturbance. The simulation aims to analyze the evolution process of surrounding rock destruction and instability in empty areas, identify the primary causes of disaster effects, develop a risk assessment and judgment model, and prevent accidents from occurring. The results of the study show that the integration of SBAS-InSAR and PSO-BP techniques for inverting rock mechanical parameters has yielded favorable outcomes in analyzing the destabilizing effect of the gob area near the mining site, and more accurately, it obtained the displacement and stress characteristics of the roof and pillars in the goaf under the mining disturbance as the mining near the empty area progresses. The simulation results demonstrate that influenced by mining disturbance, the maximum principal stress of the ore column in the void area significantly increases, primarily appearing as compressive stress. The distribution of the plastic zone indicates notably that the process of plastic deformation of the ore column leading to damage is primarily due to maximum shear stress. Evidently, the primary reason for the destabilization of the ore column is the concentration of stress resulting from mining disturbance, leading to compression and shear damage.FLAC3D simulation analysis has conclusively determined that pressure shear damage to the ore column resulting from undermining disturbance is the main cause of airspace destabilization in mining. The research methodology and analysis results provide vital theoretical support for the prevention and control measures against destabilization disasters in empty zones near mining sites, holding significant theoretical and practical value.