采动煤层覆岩往往处于不同应力状态并伴生不同的裂隙形态，并且裂隙煤岩体与瓦斯处于两相共存的渗流环境，渗流作用下复杂裂隙岩体的形变及失稳直接关系煤岩巷道的稳定性。所以，在探讨渗流-应力耦合下裂隙岩石的力学特性以及渗透能力方面，这一点显得极其关键。本文基于含瓦斯煤岩多场耦合试验系统，针对预制断续双裂隙岩石，开展了不同围压，瓦斯压力和裂隙角度组合下的断续双裂隙岩石全应力应变过程中形变及渗透率演化特征研究试验，得出以下结论：

通过开展断续双裂隙岩石不同裂隙角度下（10°、50°和90°）、不同围压（5MPa、7.5MPa和10MPa）、不同瓦斯压力（1MPa、2MPa和3MPa）的三轴渗流试验，研究了渗流-应力作用下的应力应变特征；得到了断续双裂隙岩石的峰值强度、弹性模量和泊松比随围压增长而增加；瓦斯压力减小了试样的峰值强度和弹性模量，加强了试件的泊松效应，裂隙角度与之相反。

通过分析不同试验条件下断续双裂隙岩石的渗透率演化特征，得到了渗透率随轴向应变变化呈现出缓慢降低、快速增加及急剧上升3个阶段演化规律，随体积应变变化呈缓慢降低、快速增加Ⅰ期、快速增加Ⅱ期、趋于平稳及急剧上升5个阶段演化规律。

通过正交试验研究，确定影响力学和渗透指标的关键因子。对于影响峰值强度、残余强度和泊松比程度的排序为裂隙角度>围压>瓦斯压力；弹性模量的影响程度排序为裂隙角度>瓦斯压力>围压；最小渗透率的影响程度排序为围压>瓦斯压力>裂隙角度，渗透率最大值的影响程度排序为裂隙角度>围压>瓦斯压力。

通过分析渗流-应力耦合作用下能量储存与耗散特征，得到了围压会加强岩石能量积聚，而瓦斯压力起到降低岩石储能能力的作用。裂隙角度和围压越大，弹性应变能在峰后破坏阶段能量释放越剧烈。围压越大，峰前所需的耗散能就越多，在峰后阶段所激增的耗散能量值越大。瓦斯压力越大，峰后阶段所激增的耗散能量值越小。

通过分析裂纹表观特征，得到不同工况条件下断续双裂隙岩石的破坏形式，随着围压的增加，岩桥处翼裂纹扩展路径将逐渐向试件端面靠近。随着裂隙角度的增加，破坏类型由拉破坏转为拉剪破坏，再到劈裂拉破坏的演变，破坏的剧烈程度也相应地从弱变化到较强，最后到强的转变。研究结果可为深化采动影响下含裂隙煤岩体的失稳破坏机制研究提供理论参考。

The overlying rocks of mining coal seams are often in different stress states and accompanied by different fissure patterns, and the fissured coal rock body and gas are in a two-phase coexistence of seepage environment, the deformation and destabilization of the complex fissured rock body under the seepage effect are directly related to the stability of the coal roadway. Therefore, it is especially important to study the strength, deformation and permeability of fissured rocks under Seepage-stress coupling. Based on the multi-field coupling test system of gas-containing coal rock, this paper carries out the characterization of the deformation and permeability evolution of interrupted double-fractured rock under different combinations of perimeter pressure, gas pressure and fracture angle in the full stress-strain process for prefabricated interrupted double-fractured rock, and draws the following conclusions:

The stress-strain characteristics under seepage-stress were investigated by carrying out triaxial seepage tests with different fracture angles, different perimeter pressures, and different gas pressures in interrupted bifurcated rocks; positive correlations were obtained between the perimeter pressures and the strength-deformation parameters of the specimens; the gas pressures reduced the peak strengths and elastic moduli of the specimens and enhanced the Poisson effect of the specimens, and the fracture angles were inversely correlated with each other.

By analyzing the permeability evolution characteristics of the interrupted bifurcated rocks under different test conditions, it was obtained that the permeability with axial strain changes showed three stages of evolution laws of slow decrease, rapid increase and sharp increase, and five stages of evolution laws of slow decrease, rapid increase Ⅰ, rapid increase Ⅱ, leveling off and sharp increase with volumetric strain changes.

The main factors affecting each mechanical index and permeability performance were identified through orthogonal test analysis. The influences on peak strength, residual strength and Poisson's ratio are, in descending order, fissure angle>peripheral pressure>gas pressure; the influences on modulus of elasticity are, in descending order, fissure angle>gas pressure>peripheral pressure; the factors affecting the minimum permeability are, in descending order, peripheral pressure>gas pressure>fissure angle; and the factors affecting the maximum value of permeability are, in descending order, fissure angle>peripheral pressure>gas pressure.

By analyzing the characteristics of energy storage and dissipation under seepage-stress coupling, it was obtained that the peripheral pressure enhances the rock energy accumulation, while the gas pressure plays a role in reducing the rock energy storage capacity. The larger the fracture angle and the surrounding pressure, the more drastic the energy release of elastic strain energy in the post-peak damage stage. The greater the confining pressure, the more dissipation energy is required before the peak, and the greater the value of dissipation energy that is surged during the post-peak phase. The higher the gas pressure, the smaller the value of dissipated energy surged in the post-peak phase.

By analyzing the apparent characteristics of the cracks, the damage forms of the interrupted bifid rock under different working conditions are obtained, and with the increase of the circumferential pressure, the extension path of the wing cracks at the rock bridge will be close to the end face of the specimen. With the increase of angle, the damage type changes from pull damage to pull-shear damage, and then to the evolution of cleavage pull damage, and the degree of damage changes from weak to stronger and finally to strong accordingly. The results of the study can provide a reference for the study of destabilization and damage mechanism of coal rock body containing fissures under the influence of mining.

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