Failure Mechanism Analysis of Mining-Induced Landslide Based on Geophysical Investigation and Numerical Modelling Using Distinct Element Method

Underground mining activity in the karst mountain southwestern China has induced several large-scale rocky landslides and caused serious casualties. At present, there is a lack of systematic research on formation mechanism this area using multi-method fusion technology. First, orthophoto images landslide obtained by UAV photography were used to analyze deformation characteristics landslide. Second, failure strata overlying goaf analyzed geophysical detection. Finally, response under underground UDEC numerical simulation. The results revealed that during mining, process occurred four stages: fracture expansion, subsidence collapse, shear sliding, multi-level sliding. Gently dipping soft–hard alternant blocky rock mass structure formed geological foundation landslides. accelerated fracturing stepped penetrating sliding surface. Tensile movement structural planes hard sandstone free face, weak mudstone layer, main causes slope instability mode was tension-shear fracturing, back toppling, compressive failure. In addition, propagation damaged detection consistent with simulation results. This study provides ideas for precise countermeasures disaster prevention mitigation similar area.