Study on S-wave propagation through parallel rock joints under in situ stress.

In situ stress is an important feature of underground rock masses. This paper extends the time-domain recursive method to the study of S-wave propagation through in situ stressed rock masses containing parallel joints. A linear elastic model and hyperbolic nonlinear slip model (HNSM) are first used to establish equations for wave propagation across jointed rock masses under a combination of gravitational and tectonic stress. Then, a comparison is made of the waveforms generated using the HNSM and Mohr–Coulomb slip model. Their differences are investigated and the wave propagation equation verified. Finally, parametric studies are conducted to investigate the effect of joint angle, joint number, in situ stress, and lateral pressure coefficient. The results show that the HNSM can describe the dynamic changes in the stress and their effect on the deformation behavior of the joint during the propagation of the S-wave. The effect of in situ stress on wave propagation is related to the joint angle and lateral pressure coefficient, which determine the initial stress state and contact state of the joint. [ABSTRACT FROM AUTHOR]