Dynamic disaster control of backfill mining under thick magmatic rock in one side goaf: A case study

In order to explore the control effect of backfill mining on dynamic disasters under special geological mining conditions of overlying thick magmatic rock (TMR), a three-dimensional numerical model of a panel of one side goaf in Yangliu coal mine with double-yield backfill material constitutive model was developed. The simulation results were then compared with field monitoring data. The dynamic disaster control effect of both caving and backfill mining was analyzed in three different aspects, i.e., displacement field, stress field and energy field. The results show that in comparison to the full caving mining method, the bearing capacity of the goaf after backfilling was enhanced, the backfill mining can effectively reduce the stress and energy accumulated in the coal/rock body, and the backfill mining eliminates the further moving space of TMR and prevents its sudden rupture. Before TMR fracture, the subsidence displacement of TMR was reduced by 65.3%, the front abutment stress of panel decreased by 9.4% on average and the high energy concentration zone around panel was also significantly reduced. Overall, the results of this study provide deeper insights into the control of dynamic disasters by backfill mining in mines.