Effects of joints on anisotropy of P- wave velocity, particle vibration and rock mass quality in limestone

In this study, by conducting the in situ seismic tests on limestone rock mass, the P-wave velocity and the maximum vibration of particles and anisotropy index were determined in different nine directions. Then, the rock mass was classified according DRMR classification system and the correlation between the DRMR with P- wave velocity and peak particle velocity was investigated and new experimental relationships with high correlation were presented. The seismic source is the impact caused by a weight falling. Recording the first arrival time of seismic waves and peak particle velocity in the rock mass was done by a three-component geophone. The recorded data were analyzed using the statistical method of least squares, and linear relationships with the maximum correlation coefficient between the quality of the anisotropic rock mass, P-wave velocity and peak particle velocity were obtained. The results showed that the joint sets cause anisotropy in the rock mass quality, P-wave velocity and the peak particle velocity. The rose and radar diagrams showed that the rock mass quality, P-wave velocity and peak particle velocity are higher in the direction parallel with the strike of joint sets and lower in bisector direction of the angle between the strikes of joint sets.