【作者】 徐佑林；

【导师】 康红普；

【作者基本信息】 煤炭科学研究总院 ， 采矿工程， 2014， 博士

【摘要】 论文以晋煤集团寺河矿高瓦斯煤层为工程背景，采用现场调查与测试、实验室试验、理论分析、数值模拟相结合的研究方法开展研究。主要研究内容包括：含瓦斯煤在卸围压条件下的瓦斯渗流及煤岩变形破坏规律试验，高瓦斯煤层锚固性能、巷道围岩变形破坏规律，以及瓦斯渗流与锚杆支护相互作用规律研究。研究主要得出以下结论：（1）不同瓦斯压力对煤体渗透率的影响不同，瓦斯压力越大煤体内的瓦斯渗透率越大；煤体内瓦斯渗透率随着围压的增大而降低；卸围压速度越大，瓦斯解吸速度越快，煤体渗透率越大；（2）不同瓦斯压力对煤体强度影响不同，瓦斯压力越大，煤体强度越低，发生破坏失稳前的时间越短；围压越大，煤体强度越高；卸围压速度越快，煤体发生破坏失稳需要的时间越短；（3）在高瓦斯煤层中，瓦斯压力越大对煤体的破坏作用越明显，瓦斯抽采后煤体的宏观力学性能劣化程度更高，锚固性能越低；（4）瓦斯压力越大，巷道围岩塑性区范围越大；地应力越大，巷道围岩塑性区范围越大；巷道半径越大，围压塑性区范围越大；支护阻力越大，巷道塑性区范围越小；（5）高瓦斯煤层巷道围岩开挖初期是最不稳定的阶段，容易发生煤与瓦斯突出；巷道开挖后，煤体内吸附瓦斯逐渐解吸，吸附瓦斯产生的膨胀应力逐渐降低，煤岩体有效应力逐渐增加，煤层产生收缩变形使锚杆轴力出现一定的损失，锚杆上轴力随着瓦斯压力增大呈线性衰减，需提高锚杆预应力以补偿瓦斯渗流造成的预应力损失；（6）端部锚固和加长锚固锚杆钻孔中容易聚集高浓度的瓦斯，引起瓦斯燃烧等灾害；（7）高预应力锚杆支护能有效改善巷道围岩应力状态，控制巷道围岩变形，降低锚固区煤体孔隙率，控制煤层瓦斯涌出，减少巷道瓦斯涌出量；（8）在高瓦斯煤层进行巷道掘进时，应及时采用高预应力全长锚固支护方式加强巷道支护，控制围岩的初期变形，增加煤体自身承载能力，保证巷道围岩稳定。更多还原

【Abstract】 This paper, taking the high gas-containing coal seam of Sihe coal mine of Jincheng CoalGroup as the engineering background, carries out research using the research method whichincludes live survey and test, laboratory test, numerical simulation and theoretical analysis.The paper mainly discusses the gas seepage and the coal deformation failure law test ofgas-containing coal when unloading confining pressure of coal seam, the anchorageperformance of high gas-containing coal seam, the roadway surrounding rock failure law andthe interaction law of gas seepage and bolt supporting. It concludes as follows:(1) Gaspressure, crustal stress and the speed of unloading confining pressure have an effect on thecoal permeability. The permeability rises with the increase of gas pressure or speed ofunloading pressure, but it falls with the decrease of confining pressure.(2) Gas pressure,crustal stress and the speed of unloading confining pressure have an effect on the coaldeformation failure. The coal strength falls with the increase of gas pressure or the decrease ofconfining pressure. The time before coal damage reduces with the increase of gas pressure orspeed of unloading pressure.(3) Gas pressure has an effect on the anchorage performance ofcoal. The anchorage performance degrades with the increase of gas pressure. Themacro-mechanical properties of coal will degrade after gas drainage, causing anchorageperformance to degrade.(4) The plastic zone, decreasing with the increase of supportingresistance, augments with the increase of gas pressure, crustal stress or the radius of roadway.(5) The early excavation of high gas-containing coal seam is the most unstable moment,which causing coal and gas outburst easily. After excavation of roadway, the effective stressof coal increases gradually with the decrease of swelling stress due to gas desorption. Theshrinkage of coal reduces the axial stress of rock bolt which presents liner attenuation with theincrease of gas pressure.(6) The end anchorage and the elongation of rock bolt will producehigh concentration gas when the drilling work is done, which may cause disaster (such as gascombustion).(7) High pre-stressed bolt support can effectively improve the stress state andsurrounding rock deformation of roadway, control and reduce the coal porosity of boltingzone, control of coal seam gas emission.(8) The anchorage of full length with high preload is needed to strengthen roadway supporting when driving into the high gas-containing coal seam.Then the desorption speed of gas and the initial deformation of coal can be controlled toensure roadway stable.更多还原