Optimization of the Flexible Mesh Support Processing Parameters in Downward Approach Mining Drift by Numerical Simulation

The support methods in downward approach mining drift have always suffered from problems of inflexible operation, with high substantial costs and poor supporting efficiency under high ground stress and repeated engineering disturbances. In this work, a novel flexible mesh support schematic was designed and introduced in downward approach mining drift. Based on extensive field investigations and sampling experiments conducted within the mining region, material models and contact models for defining the complex hidden joint structure in a metal mine were established and developed to simulate the stress distributions of the designed flexible mesh support. The deformation and failure behavior of the flexible mesh support under the effect of high ground stress were investigated and its feasibility was evaluated. The results show that the flexible mesh support system exhibits a distinct control effect on the deformation of perimeter rock. The perimeter rock deformation decreases by nearly 46.0% after the flexible mesh support, and the maximum horizontal displacement is 60 mm. An optimized flexible mesh support scheme for downward approach mining drift was obtained and confirmed by industrial tests. This work provides a flexible mesh support technology for downward approach mining drift, which can not only enhance the safety of downward approach mining drift operations, but also significantly improve construction efficiency.