Room-and-pillardepillaring using backfill to reduce subsidence
The coal mining in Santa Catarina State is room-and-pillarunderground mining method, but retreat mining is not allowed because the subsidence consequences and its effect on the surface above the mining area.The subsidence could affects some agriculture areas, buildings, and streams and ground water.The backfill could be the solution to reduce the subsidence amount or even avoid it.The backfilling process must have be made before retreating operation, due safety and ground movement.Therefore, some entries are left empty and others completely full of material, and the retreat and depillaring process has be done at the empty entries.The aim of this paper is to study the effect of the backfilling process to reduce the subsidence that is the cause of depillaring operation in a mine section.The geometry of the cuts into the pillar geometry considered the maximum cut depth for the CM-14 Joy continuous miner, which is about 8m for safety reasons.The proposed geometry recovers about 20-45% of the pillar area, depending the depth and number of cuts.A 3D numerical model had built to study the pillar behavior and confinement estimation.The results showed that the back increases the confinement of the pillar and its strength.Also, could reduce the subsidence.
backfill coal mining pillar recovery numerical modeling
Andre C.Zingano
Universidade Federal do RioGrande do Sul
国际会议
The 34th International Conference on Ground Control in Mining (ICGCM) 2015(34届国际采矿岩层控制会议)
焦作
英文
239-247
2015-10-17（万方平台首次上网日期，不代表论文的发表时间）