关键词: 金川二矿区, 复杂采矿条件, 多中段开采, 水平矿柱, 地压活动

Abstract: For the reality of multi-level mining in Jinchuan No.2 mine under the complicated geological and mining conditions, three-dimensional finite difference code, the mechanism, on which temporary pillar support controlled redistribution of the ground pressure and convergence displacement in mined-out structure, was found, and the change in distribution of the pillar's stress and deformation was obtained as the horizontal pillar was thinned and disappeared due mining in sublevel downwards. The results showed that at the beginning of pillar formation, it played important role in controlling the convergence between the hanging wall and footwall surrounding rock of mined-out range, but obvious stress concentration occurred in the conjunction of the pillar and surrounding rock. After recovering the pillar, the convergence deformation of the footwall increased obviously in comparison with the hang wall's deformation, but it could not caused catastrophic ground pressure movement.

Key words: Jinchuan No.2 mine, Complicated mining conditions, Multi-level mining, Horizontal pillar, Ground pressure activity