回采工作面沿空留巷爆破切顶卸压实践

Practice of Blasting Roof Cutting Pressure Relief for Gob-side Entry Retaining in Mining Face

煤层掘巷留保护煤柱开采,不仅会造成应力集中,还会损失高达10%~30%的煤炭资源。通过对比德丰源煤矿1334采面运输巷实施切顶卸压沿空留巷的效果总结、分析,得到巷道顶底板最大移近373 mm,非回采侧最大移近63 mm,且巷道顶板8 m范围内没有发生离层现象,该巷道可为下一回采工作面安全回采提供可靠保障。沿空留巷爆破切顶卸压有利于解决煤柱应力集中、提高煤炭回采率、缓解采掘接替紧张、防止煤柱自燃、改善矿井安全生产条件、提高煤炭开采的经济效益,为矿井无煤柱安全高效开采奠定了基础。

Through the summary and analysis of the effect of implementing roof cutting pressure relief gob-side entry retaining in the haulage drifts of the 1334 mining face of Defengyuan Colliery,it is found that the maximum displacement of the roadway roof and floor is nearly 373 mm,the maximum displacement on the non-mining side is nearly 63 mm,and there is no separation phenomenon within 8 meters of the roadway roof,which can provide reliable guarantee for the safe mining of the next mining face.Being conducive to solving the stress concentration of coal pillars,improving coal recovery rate,alleviating the tension of mining and replacement,preventing spontaneous combustion of coal pillars,improving the safety production conditions of mines,and increasing the economic benefits of coal mining,the blasting roof cutting pressure relief for gob-side entry retaining have laid the foundation for safe and efficient mining without coal pillars in mines.