【摘要】 基于岩体裂隙渗流-劈裂-损伤耦合效应是引起岩体工程高压突水、水力劈裂等地质灾害的重要原因,研究高水压下岩体裂隙的劈裂损伤机理和各向异性渗流特性,建立岩体裂隙渗流-劈裂-损伤耦合理论模型。将损伤应力场和渗流场作为2个子系统,采用间接耦方法构建岩体裂隙渗流-劈裂-损伤耦合数值模型。将模型应用于山西省长治市潞安王庄矿3号煤4309工作面高压注水软化顶煤工程,对高压注水下煤岩体的渗流-劈裂-损伤耦合响应规律进行研究。研究结果表明:所建模型反映了渗透压对岩体柔度张量的贡献和翼形裂纹扩展对裂隙岩体渗透张量演化的贡献;在高渗透压条件下,煤岩的应力场会发生很大变化,甚至可能改变煤岩应力拉压状态;高渗透压改变了煤岩裂纹结构,导致煤岩破裂是高压注水软化顶煤的基本原因;潞安王庄矿3号煤4309工作面的合理注水压力为7 MPa左右,这在现场注水现场试验中得到证实。更多还原

【Abstract】 Considering that the coupling effect of seepage-splitting-damage of rock mass fractures is the key reason of geological hazard, such as high pressure water burst of rock engineering, hydraulic fracturing, and so on, the splitting damage mechanism of rock mass fractures and anisotropic seepage characteristics under high water pressure were studied. The coupling theory model for seepage-splitting-damage of rock mass fractures under high water pressure was established, in which the contribution of seepage pressure to flexibility tensor of rock mass and the contribution of wing crack extension to permeability tensor evolution could be reflected. Taking damage stress field and seepage field as two subsystems, indirect coupling method was adopted to establish numerical model of splitting-damage-seepage of rock mass fractures. The model was applied in high pressure injection water to soft top coal in Coal 3 of No 4309 workface in Wangzhuang Mine of Lu’an Coal Mining Group, coupling response between seepage and damage mechanism under high water pressure was studied. The results show that under the high water pressure, the stress field of coal changes sharply, even the state of tensile and pressure in coal is changed. The coal fractures structures changed by high permeable pressure give rise to coal fracture, which is the basic mechanism of high pressure injection water to soft top coal. Through coupling analysis, the rational water injection pressure for Coal 3 of No 4309 workface in Wangzhuang Mine is about 7 MPa, and this result is testified by field test.更多还原