When the deep tunnel is excavated, the pressure of the confined water is relatively high, causing the water inrush to have a hydraulic fracturing effect. The method of theoretical analysis was adopted to study this effect. A mechanical model for fracturing water inrush under blasting excavation conditions was established. The water inrush under this condition is the result of the combined action of static load (water pressure and in situ stress) and dynamic load (explosive stress wave). According to whether the normal stress on the hydraulic crack surface was tensile stress or compressive stress, two types of water inrush were proposed: water inrush caused by tensile-shear damage and water inrush caused by compression-shear damage. These two types of critical water pressures were calculated separately. The relationship between critical water pressure, in situ stress, and blasting disturbance load was given, and a pore water pressure splitting factor was introduced in the calculation process. The theoretically obtained critical water pressure had been verified in the case of water inrush in a deep-buried tunnel. The established theory can guide field practice well.

中文翻译：

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隧道爆破突水水力压裂作用的力学机制

深部隧道开挖时，承压水压力较高，使突水产生水力压裂作用。采用理论分析的方法来研究这种效应。建立了爆破开挖工况下压裂突水力学模型。该工况下的突水是静载荷（水压和原位）共同作用的结果。应力）和动态载荷（爆炸应力波）。根据水力裂缝表面的法向应力是拉应力还是压应力，提出了两种突水类型：拉剪损伤引起的突水和压剪损伤引起的突水。这两种临界水压分别计算。给出了临界水压力、地应力和爆破扰动载荷之间的关系，并在计算过程中引入了孔隙水压力分裂因子。理论得到的临界水压已在深埋隧道突水情况下得到验证。建立的理论可以很好地指导现场实践。