长春兴煤矿应力叠加区端头煤柱破碎机理及控制技术

Mechanism and Control Technology of Coal Pillar Fragmentation at the End of Stress Superposition Zone in Changchunxing Coal Mine

长春兴煤矿307工作面受多重集中应力影响,尾端头煤柱垮落严重,应力区顺槽顶板下沉断裂、两帮煤柱收敛等,严重制约工作面安全快速推进。通过技术研究,分析了端头区围岩破碎机理,并根据生产现状,对端头区围岩采取卸压支护+柔性注浆+自移式钢棚联合支护技术。实际应用表明,采取联合支护技术后,端头区悬顶面积减小至1.2 m^(2),端头煤柱垮落长度减小至0.8 m,超前30 m范围内回风顺槽顶板下沉量减小至0.13 m,两帮收敛量减小至0.21 m,支护效果明显。

The 307 working face of Changchunxing Coal Mine is affected by multiple concentrated stresses.The tail end coal pillar collapses seriously,the roof of the stress zone sinks and breaks,and the two-side coal pillars converge,which seriously restricts the safe and rapid advancement of the working face.Through technical research,the fracture mechanism of surrounding rock in the end area is analyzed.Accord⁃ing to the production status,the combined support technology of pressure relief support+flexible grouting+self-moving steel shed is adopted for the surrounding rock in the end area.The practical application shows that after the combined support technology is adopted,the suspended roof area in the end area is reduced to 1.2 m^(2),the caving length of the end coal pillar is reduced to 0.8 m,the roof subsidence of the return air crossheading within 30 m ahead is reduced to 0.13 m,and the convergence of the two sides is reduced to 0.21 m.The support effect is obvious.