Evaluation of safety and deformation characteristics of cemented tailings backfill mining disturbed area near shafts: a case study in China

Abstract

To evaluate the safety conditions and deformation characteristics of the cemented tailings backfill (CTB) mining disturbed area near shafts of Taohuazui Gold Mine in China, an analytic hierarchy process—fuzzy comprehensive evaluation (AHP-FCE) model for disturbance degree and safety evaluation of backfill mining was established, the historical and current backfill mining processes were simulated based on 3DEC. The theoretical analysis results were verified by field monitoring during the industrial test. The results show that: (1) More than 80% of historical backfill stopes have a weak disturbance (level II) to the shafts, the distance between stope and shafts (C1) and the blasting method (C3) have the most significant influence on the evaluation results. (2) The numerical simulation results validate the rationality of the AHP-FCE model and its evaluation results, and the shafts are in a micro-disturbance deformation state of 1–3 mm, which does not exceed the allowable value. (3) The theoretical analysis results are consistent with the field monitoring results, and the disturbance degree and its variation trends induced by the CTB mining are gentle. At present, the overall safety and stability of the shafts and its adjacent areas are good.