金刚石串珠绳锯切割煤层卸压渗流规律分析

Analysis of Pressure Relief and Seepage Law of Diamond Wire Saw Cutting Coal Seam

金刚石串珠绳锯切割煤层可以实现连续性大面积煤层割缝,为了获得割缝后煤层内部的卸压渗流规律,通过煤体瓦斯渗流试验,得出不同损伤煤样的应力-渗透率拟合公式,并在此基础上采用FLAC^(3D)数值模拟方法,分析割缝后煤层的应力及渗透率分布规律.模拟结果表明:煤层割缝后,缝槽上方和下方的煤岩体应力得到释放,形成卸压区,且卸压效果与缝槽的垂直距离成反比,缝槽左右两侧出现应力集中现象;随着割缝工作面的推进,卸压区与渗透率升高区的范围逐渐扩大;随着缝槽数量的增多,煤层应力降低值和渗透率升高值越大,即增加缝槽数量可以获得更好的卸压增透效果.该研究成果对金刚石串珠绳锯切割煤层的工程实践具有一定指导意义.

Continuous large-area seam cutting can be realized by diamond wire saw.In order to obtain the pressure relief and seepage law of the coal seam after slitting,the stress-permeability fitting formula of different damaged coal samples are obtained by gas seepage test.On this basis,the FLAC^(3D) numerical simulation method is used to analyze the stress and permeability distribution law of the coal seam after slitting.The simulation results show that stress concentration zones appear on the left and right sides of seam after slitting,the pressure relief effect is inversely proportional to the vertical distance of the slot.With the advance of the working face,the range of pressure relief area and permeability increasing zone of the coal seam gradually expands.As the seam slots increases,the stress reduction value and the permeability increase value of coal seam increase,that is,the increase of the number of seam slots can obtain better effect of pressure relief and reflection improvement.The research results have guiding significance for the engineering practice of diamond wire saw cutting coal seam.