高水压与高应力对岩石应力波传播速度的影响

Influence of High Water Pressure and High Stress on Stress Wave Propagation Velocity of Rock

深部高水压岩体工程爆破开挖时,围岩体承受高水压、高地应力和爆破动载荷共同作用的理论研究远落后于工程实践。因此,自研试验系统对红砂岩进行了应力波传播试验。结果表明,当冲击速度和轴向静应力一定时,随着水压的增加,红砂岩应力波波速逐渐增大,波速随水压的增加呈二次函数变化;在拟合函数中,二次项系数、一次项系数与轴向静应力之间呈线性相关,常数项与轴向静应力之间呈非线性相关;对于初始损伤较小的红砂岩,水压的存在导致岩石内部的裂隙被挤压,增强了岩石波阻抗,有利于应力波在岩石试件中的传播。

When deep rock mass engineering with high water pressure was excavated by blasting,the theoretical research on the combined action of high water pressure,high geostress and blasting dynamic load on the surrounding rock body is far behind the engineering practice.Therefore,the stress wave propagation test of red sandstone was carried out in the self-developed test system.The results show that when the impact velocity and axial static stress are constant,the stress wave velocity of red sandstone gradually increases with the increase of water pressure,and the wave velocity changes as a quadratic function with the increase of water pressure.In the fitting function,the coefficient of quadratic term and the coefficient of primary term are linearly related to the axial static stress,and the constant term is nonlinearly related to the axial static stress.For the red sandstone with small initial damage,the existence of water pressure causes the cracks in the rock to be squeezed,which enhances the rock wave impedance and is conducive to the propagation of stress waves in the rock specimen.