Dynamic behaviour of new anchor cable ribbed rockfall retaining walls on rock shed

Abstract

This study investigates the dynamic behaviour between a rockfall and a new anchor cable ribbed rockfall retaining wall on a rock shed, by way of numerical simulations involving the coupling between the PFC3D (discrete-element method (DEM)) and Flac3D (finite-difference method (FDM)) software programs. The novel structure is modelled by the FDM through the zone element, while the rockfall and the buffer layer are modelled by the DEM through the ball element. The numerical results show that three stages of the rockfall movement were modelled: movement, impact and stagnation. The rockfall falls on the slope, impacting the buffer layer on the top of the rock shed, before rebounding to the anchored rockfall retaining walls (with a height lower than 2 m). Then, the stress and deflection can be unified and related to the impact velocity of the rockfall to examine the stability of the structure. The rockfall radius is the dominant of the three parameters (rockfall shape, rockfall radius and impact velocity). While the study focuses on a specific case study, the results provide valuable guidelines for future applications of the proposed combined structure for railway transportation protection.