Shaanxi Binchang Mining Group Co., Ltd.
Shaanxi Binchang Mengcun Mining Co., Ltd.

以彬长矿区孟村煤矿为背景,针对煤层上覆坚硬难垮顶板瞬间破断诱发冲击灾害的风险,创新应用井上下立体联合卸压技术。通过地面L型水平井分段压裂对高位关键层坚硬顶板实施压裂改性,以及井下顶板定向长钻孔水力压裂及深孔预裂爆破对中、低位关键层坚硬顶板进行等距破断弱化,破坏岩层的整体性并降低破断强度。结合煤层大孔径钻孔卸压,阻断静载荷积聚及动载荷传递通道,从源头上消除(减小)冲击危险,开辟了冲击地压科学防控的新途径。实践表明,实施立体联合卸压方法消除了工作面上覆坚硬顶板岩层难跨悬顶积聚载荷,微震频次显著下降且杜绝了1×104J以上微震事件,为具有坚硬顶板破断诱发冲击地压风险的类似矿井提供了参考。

Taking Mengcun Coal Mine in Binchang mining area as a background, and aiming at the risk of impact disastercaused by instantaneous rupture of coal seam overlying’ s hard and difficultly-collapsed roof, this paper innovatively appliesthe spatial joint pressure relief technology up and down the well. The hard roof of high-level key stratum is modified bystaged fracturing of L-shaped horizontal well on the ground, and the hard roof of middle and low-level key stratum is weakened by directional long-hole hydraulic fracturing and deep-hole prefracture blasting of underground roof, which destroys theintegrity of rock stratum and reduces the fracture strength. Combined with the pressure relief of large-hole drilling in coalseam, the static load accumulation and dynamic load transmission channels are blocked, which eliminates ( reduces) the impact danger from the source, opens up a new way for scientific prevention and control of rock burst. The practice has provedthat the implementation of spatial joint pressure relief can eliminate the difficultly collapse and load accumulation of overlaying hard roof rock in working face, considerably reduce micro-seismic frequency and avoid over 1 × 104J micro-seismic incidence. Our research is of reference for preventing and controlling rock burst disasters induced by the fracture of hard roofin similar mines.