水力压裂切顶卸压参数模拟研究

Simulation Study of Hydraulic Fracturing Top Cutting and Pressure Relief Parameters

为了解决坚硬顶板在矿井开采过程中引发的困扰,利用数值模拟软件对水力压裂过程进行模拟,发现水力压裂下裂缝扩展分为三个阶段,分别为能量累计阶段、钻孔起裂阶段、裂缝扩展阶段,伴随着三个阶段,裂缝先起裂后向着最大水平主应力方向发生偏转。同时通过对不同水平应力差下裂缝张开度、裂缝偏转角进行数值模拟研究发现,张开度随着水平应力差的增大逐步减小,而裂缝偏转角随着水平应力差逐步增大,为矿井水力压裂方案的实施提供一定的理论依据。

In order to solve the problems caused by the hard roof in the mining process of the mine,the hydraulic fracturing process was simulated by using numerical simulation software,and it was found that the fracture propagation under hydraulic fracturing was divided into three stages,namely,the energy accumulation stage,the borehole initiation stage,and the fracture propagation stage.With three stages,the fracture first started and then deflected towards the maximum horizontal principal stress direction.At the same time,through the numerical simulation study of fracture opening and fracture deflection angle under different horizontal stress differences,it is found that the opening decreases gradually with the increase of horizontal stress difference,while the fracture deflection angle increases gradually with the increase of horizontal stress difference,which provides a certain theoretical basis for the implementation of mine hydraulic fracturing scheme.