关键词: 地震波传播, 非线性节理, 时域递归法, 连续屈服模型

Abstract: It is important to consider an aseismic issue, which is that transflective properties of the seismic wave propagating through joints embedded in rock in underground rock engineering. However, there is very limited research on transflective properties by using the continuously yielding nonlinear joints model. In this paper, a continuously yielding (CY) model was developed based on the time-domain recursive method (TDRM) for S wave using a nonlinear Coulomb-slip (MC) model. Verification of TDRM-based results was conducted in comparison with the simulated results via 3DEC code. Meanwhile, the influence parameters were also discussed. Finally, the results from MC model and CY model were compared under an idealised impulse excitation and a real ground motion record, respectively. It can be seen that TDRM-based results show good agreement with the simulated results by 3DEC, which proves that TDRM is reliable to study the subsequent parameters. In addition, CY model is significantly influenced by parameters of normal stress, incident wave amplitude, initial joint stiffness and joint spacing, respectively. Compared with MC model, CY model can better describe complex joint behaviours in the wave propagation, such as tangential stiffness degradation, shear strength deterioration, normal stress dependence and the hysteresis effect. Therefore, research results can provide useful references for the seismic design and analysis of rock underground engineering.

Key words: seismic wave propagation, nonlinear joint, time-domain recursive method, continuously yielding model