(1. State Key Laboratory of Geomechanics Geotechnical Engineering，Institute of Rock and Soil Mechanics，Chinese Academy of Sciences，Wuhan，Hubei 430071，China；2. University of Chinese Academy of Sciences，Beijing 100049，China)
Abstract：In order to avoid the outward waves being reflected back into the simulated domain at the artificial boundaries，the absorbing boundaries must be used in applying the granular discrete element method(PFC). To consider the various radii of particle elements on the artificial boundaries and the irregular boundary surfaces，the equivalent equation applicable for this discrete elements method was obtained based on the continuum viscous boundary condition. The calibration factors were introduced into the equivalent equation and a method to determine their values necessary for the optimum wave absorption was proposed. The joint network models of bedding and reverse bedding rock slopes were established with the synthetic rock mass approach (SRM). The viscous boundary conditions were built on the artificial boundaries in PFC models of rock slope based on the proposed method. At the same time，the seismic failure process of bedding and reverse bedding rock slopes with orthogonal secondary rock joints were simulated and systematic analyses of the seismic failure mechanism were conducted.
2017, Vol. 36 
