我国是煤炭消费大国，深部开采逐渐成为我国煤炭开采的新局面，随着开采深度的不断增加，瓦斯赋存条件更加复杂。我国煤矿瓦斯事故频发，瓦斯抽采作为降低瓦斯事故的重要手段之一被广泛运用，而钻孔布置参数影响着瓦斯抽采效率及瓦斯渗流过程，因此必须明确钻孔布置参数对煤体变形及瓦斯吸附解吸渗流规律的影响，对提高瓦斯灾害防治水平具有一定的指导意义。

实验煤样选自澄合某矿，利用三维光学散斑技术分析不同参数煤体单轴加载过程中的变形破坏特征，得出随着钻孔直径和钻孔角度增大，煤体抗压强度都减小；当钻孔直径和钻孔角度较小时，破坏形式主要为拉伸破坏；当钻孔直径和钻孔角度较大时，破坏形式主要为拉伸和剪切复合破坏。

采用自主研发的煤层气流固耦合综合测试实验平台，得出随着钻孔角度增大，煤体吸附、解吸变形量呈现上升趋势，渗透率增大；随着钻孔直径增大，吸附变形量增加，解吸变形量有增有减，渗透率的变化区间为2.12~3.66×10^-16m²；随着瓦斯压力增大，吸附、解吸变形量呈现上升趋势，渗透率与变形量呈现正相关的变化趋势。分析煤体瓦斯运移各阶段变化，得到瓦斯吸附量随着钻孔角度增大呈现上升趋势，解吸率依次为86.7%、84.29%、84.21%、82.87%，煤体的瓦斯流量呈现增加趋势；随着钻孔直径增大，煤体瓦斯吸附量变化范围为2.45ml/g~2.67ml/g，瓦斯解吸率逐渐增加，瓦斯流量增加；随着瓦斯压力增大，瓦斯吸附量呈增加趋势，煤体瓦斯解吸量呈现增加的趋势，煤体解吸量峰值是最小值的1.76倍，瓦斯流量的变化区间为9.54ml/min~16.47ml/min。

通过COMSOL数值模拟软件验证了物理实验结果，二者的变化规律具有较好的一致性；通过现场验证，得到随着抽采时间的增加，瓦斯压力逐渐减小，抽采孔径越大，有效抽采半径的变化幅度越大。研究成果为优化煤层瓦斯抽采钻孔布置、提高瓦斯抽采效率、增强矿井瓦斯灾害防治水平提供了一定的工程实践意义。

China is a big country of coal consumption. Deep mining has gradually become a new situation of coal mining in China. With the increasing depth of mining, the conditions of gas occurrence are more complicated. Gas accidents occur frequently in coal mines in China.Gas extraction is widely used as one of the important means to reduce gas accidents, and borehole layout parameters affect gas extraction efficiency and gas seepage process. Therefore, it is necessary to clarify the influence of borehole layout parameters on coal body deformation and gas adsorption and desorption seepage law, which has certain guiding significance for improving the level of gas disaster prevention and control.

The experimental coal sample was selected from a mine in Chenghe. The deformation and failure characteristics of coal with different parameters during uniaxial loading were analyzed by three-dimensional optical speckle technique. It is concluded that the compressive strength of coal decreases with the increase of borehole diameter and borehole angle. When the borehole diameter and borehole angle are small, the failure mode is mainly tensile failure. When the borehole diameter and borehole angle are large, the failure mode is mainly tensile and shear composite failure.

By using the self-developed comprehensive test platform for fluid-solid coupling of coalbed methane, it is concluded that with the increase of drilling angle, the deformation of coal adsorption and desorption shows an upward trend, and the permeability increases. With the increase of borehole diameter, the amount of adsorption deformation increases, and the amount of desorption deformation increases and decreases. The change range of permeability is 2.12 ~ 3.66 × 10-16 m2. As the gas pressure increases, the amount of adsorption and desorption deformation shows an upward trend, and the permeability and deformation show a positive correlation trend. By analyzing the changes of each stage of gas migration in coal body, it is found that the gas adsorption capacity increases with the increase of drilling angle, and the desorption rate is 86.7 %, 84.29 %, 84.21 % and 82.87 % respectively, and the gas flow of coal body shows an increasing trend. With the increase of borehole diameter, the gas adsorption capacity of coal body varies from 2.45ml/g to 2.67ml/g, the gas desorption rate increases gradually, and the gas flow rate increases. With the increase of gas pressure, the amount of gas adsorption shows an increasing trend, and the amount of coal gas desorption shows an increasing trend. The peak value of coal desorption is 1.76 times the minimum value, and the change range of gas flow is 9.54ml/min~16.47ml/min.

The physical experiment results are verified by COMSOL numerical simulation software, and the variation rules of the two are in good agreement. Through on-site verification, it is obtained that with the increase of extraction time, the gas pressure gradually decreases, and the larger the extraction aperture, the greater the change range of the effective extraction radius. The research results provide a certain engineering practical significance for optimizing the layout of coal seam gas extraction boreholes, improving the efficiency of gas extraction, and enhancing the level of mine gas disaster prevention and control.

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