Three-dimensional Seismic Displacement Analysis of Rock Slopes based on Hoek-Brown Failure Criterion

Seismic force is one of the main factors resulting in the slip failure of steep rock slopes. In this paper, the seismic displacement analysis of rock slopes is carried out by virtue of the kinematical theorem of limit analysis and the Newmark method. It is assumed that the slope has a curvilinear cone-shaped failure mechanism and its materials are subjected to the Hoek-Brown failure criterion. The generalized tangential technique is employed to obtain equivalent parameters from the Hoek-Brown criterion. According to the three-dimensional failure mechanism, the internal energy dissipation and external work are respectively calculated, and the effect of horizontal seismic force is included by using the equivalent pseudo-static method. Subsequently, the yield acceleration is calculated for three-dimensional failure mechanism, and the results are shown to be valid when compared with the previous solutions. Parameter analysis is used to represent how the Hoek-Brown criterion parameters impact on the yield acceleration. The failure mechanism is also obtained during the process of limit analysis, and a dimensionless coefficient is adopted to investigate the influence of it on the seismic displacements of slopes. The results of calculations are given for a series of actual seismic waves and compared with the results calculated from empirical formula.