深埋冲击地压矿井多关键层结构稳定性及防冲减震技术研究

RESEARCH ON THE STABILITY OF MULTI KEY LAYER STRUCTURES AND ANTI IMPACT AND VIBRATION REDUCTION TECHNOLOGIES IN DEEP BURIED ROCKBURST MINES

  • 摘要: 为给深埋冲击地压多关键层矿井安全生产创造有利条件,基于符拉索夫板理论开展多关键层结构稳定性研究,发现厚硬岩层内部拉应力最大值受采空区短边影响较大,且厚硬岩层中拉应力极值随巨厚覆岩层厚度的增大而减小。另外,研究认为3100工作面关键层一(厚度5~22 m)在采空区走向边宽度达到20~25 m左右时会发生破断;关键层二(厚度33~53 m)在采空区走向边宽度达到90~100 m左右时会发生破断。然后通过现场实践的研究方法,针对不同层位厚硬顶板提出了低位顶板爆破卸压,高位定向水力压裂卸压的防冲减震措施。最后,对比分析门克庆煤矿同采区的3100工作面与3102工作面防冲措施卸压效果,采用多关键层卸压措施的3100面比未采取多关键层卸压措施的3102面每米微震频次降低了9.5%,每米微震能量降低了86.2%。研究成果已应用于门克庆矿井,取得了良好的效果。

     

    Abstract: In order to create favorable conditions for the safe production of multi key layer mines with deep buried impact ground pressure, a study on the stability of multi key layer structures was carried out based on the Vlasov plate theory. It is found that the maximum tensile stress inside thick hard rock layers is greatly affected by the short side of the goaf, and the maximum tensile stress in thick hard rock layers decreases with the increase of the thickness of the thick overlying rock layer. In addition, research suggests that the key layer one (thickness 5~22 m) of the 3100 working face will break when the width of the goaf reaches about 20-25 m; key layer two (thickness 33~53 m) will break when the width of the goaf reaches about 90~100 m. Then, through on-site practical research methods, anti impact and shock absorption measures were proposed for different layers of thick and hard roof, including low-level roof blasting pressure relief and high-level directional hydraulic fracturing pressure relief. Finally, a comparative analysis was conducted on the pressure relief effects of the 3100 and 3102 working faces in the same mining area of Menkeqing coal mine. It was found that the 3100 face, which adopted multiple key layer pressure relief measures, had a 9.5% reduction in microseismic frequency per meter and an 86.2% reduction in microseismic energy per meter compared to the 3102 face, which did not adopt multiple key layer pressure relief measures. The research results have been applied to the Menkeqing mine and achieved good results.

     

/

返回文章
返回