地下工程中由控稳到控水的断裂屏障机制

Barrier effects caused by fault on excavating-induced stress & edformation and mechanism of resulting groundwater inrush

结合工程实例分析了原始地质条件下的不导水断层在采动影响下透水并最终导致突水事故发生的作用机理。研究表明,在一定条件下,断裂破碎带成为围岩变形和采动应力传播的屏障。这种屏障作用的结果使得断裂带内岩体变形强烈,变形梯度大,开挖空间与断裂带之间围岩变形和采动应力集中加剧,这容易引起断裂带含有原生结构面的构造岩体和存在断层伴生裂隙的围岩变形错动,并进一步导致地下水导升。工程实例证明了这一分析的合理性。

Combined with engineering cases, the mechanism of inrush through fault which is water-inconductive in initial geological condition, has been studied. It is found that the fault zone can act as a barrier of excavating-induced stress & deformation under some conditions. The barrier effect may cause intense deformation, high deformation gradient in rockmass within the fault zone, more intense deformation and stress concentration between the excavated space and the fault. All of them may easily arouse rockmass deformation and geological structure slip within and near the fault zone, and furthermore lead to groundwater inrush. The rationality of analyses mentioned above has been confirmed by the specific engineering cases.