声波波速变化可有效表征岩体损伤程度。通过对岩样进行人工预损，利用声波检测标定岩样的不同损伤程度，然后通过三轴压缩试验来研究不同损伤程度下岩石的力学特性，建立了声波速度下降幅度与岩体力学参数变化幅度间的关系。研究表明，当岩样的声波速度下降5%～8%时，黏聚力c值降低15%～25%，内摩擦角? 值则升高14%～32%，因此，用声波速度的下降幅度来描述岩体参数的变化是可行的。根据现场实测的岩体损伤区内的声波速度的变化值，可以从一定程度上估计岩体参数的跌落情况，从而更进一步地说明损伤区内岩体的承载力。

The damage degree can be characterized by the acoustic wave velocity of rock masses effectively. The rock samples are pre-damaged by the artificial cyclic loading, and the damage degree is determined by acoustic determining method. Then the mechanical properties of rock samples under different damage degrees are studied through triaxial compression test. The relationship between the decrease of acoustic wave velocity and the variation of the mechanical parameters of rock masses is established. The results show that, when the acoustic wave velocity of rock samples decreases by 5%-8%, the value of the cohesive of rock samples will reduce by 15%-25%, and the internal friction angle will increase by 14%-32%. It is shown that using the reduction of the acoustic wave velocity to describe the change of the rock mass parameters is feasible, because the rock is hardly damaged in the case of acoustic wave testing. So according to the field measurement data of the variation of the acoustic wave velocity, the change of rock mass parameters can be estimated to a certain extent, the bearing capacity of rock mass in damage zone can be further illustrated.