关键词: 阶段矿房法, 大跨度凿岩硐室, 数值模拟, 稳定性, 深孔爆破

Abstract: A copper mine in Anhui Province adopts a large-diameter vertical deep-hole stage chamber mining method.The first mining stope has a mining depth of 800 m and a span of 30 m.The blasting vibration greatly disturbs the surrounding rock mass and the stope structure，and the rock mass energy is induced by the large blasting process. The release and transfer are likely to form the main structural instability of the stope and threaten the safety of mining.In order to study the stability of large-span rock drilling chamber under the action of dynamic and static combination，according to the actual situation of the mine，based on FLAC3D 5.0 numerical simulation software，numerical simulation analysis of the stability of the 201 large-span rock drilling chamber in the first mining section of the copper mine under dynamic and static load combination is done，and the comparison analysis of the numerical simulation results and on-site monitoring results are conducted.The study results show that:during the mining process，the maximum principal stress and plastic zone are mainly concentrated on the column，the displacement of the roof is increased after the support of the column is lost，and the support of the column is obvious；after the mining is completed，all of the columns are recovered and the displacement of the roof is reached，the maximum value of the column becomes the main support structure，the rock drilling chamber is relatively stable during the whole mining process，and the analysis results are consistent with the monitoring results.It is recommended that the width of the rock-filled chamber column should be appropriately increased before the subsequent mining and the joint support of the anchor net can be implemented to improve the pressure resistance；the influence of the blasting vibration on the roof can be reduced by adjusting the blasting parameters， and long anchor cable support of the roof of the middle part of the rock chamber can be conducted；the monitoring of the vulnerable areas in the simulation and monitoring results can be carried out to provide valuable reference information for avoiding geostress disasters in the subsequent mining process.

Key words: Stage chamber mining method, Large-span rock drilling chamber, Numerical simulation, Stability, Deep-hole blasting