Numerical Simulation and Observational Damage Rating In Sublevel Shrinkage Crosscuts Under High-Stress Condition at Lac Des Iles Mine

Lac Des Iles Mine transitioned to the sublevel shrinkage mining method in 2016. New geotechnical challenges have been recently encountered at deeper levels due to high mining-induced stress around crosscuts. Several transverse crosscuts have sustained significant wall deformation, corner crushing, and instances of ground support failure. This study investigates the performance of transverse crosscuts in a sublevel under high-stress conditions, focusing the progression of rock mass damage during development and production stages. The Map3D modeling software was utilized to assess mining-induced stress redistribution and rock mass damage. Simulation results were validated through underground observations, revealing consistent patterns of stress evolution and damage progress across the level. The findings showed that mining induced damage initiated in central crosscuts and progressively affected other crosscuts as mining activities advanced.