Seismic stability of reinforced soil slopes using the modified pseudo-dynamic method

The limit equilibrium analysis through the horizontal slice method is used to study the seismic stability of reinforced soil slopes by satisfying the equilibrium of the horizontal and vertical forces as well as moments. Unlike the pseudo-static (PS) method, the pseudo-dynamic method consideres the effects of time and phase difference of the P and S waves propagation inside the soil mass. In this paper, the PS, the conventional pseudo-dynamic (CPD), and the modified pseudo-dynamic (MPD) methods are used to study the seismic stability of reinforced soil slopes. In addition, the equivalent linear method is implemented to analyze the site response for the purpose of calculating the soil dynamics parameters required for the seismic stability analysis of soil slopes via the MPD method. A MATLAB code is developed to calculate via the abovementioned methods. Using the log-spiral slip surface, this code considers the distribution of reinforcements as uniform and variable spacing. In addition, the effect of surcharge pressure on the seismic stability of the slope is included in this study. The obtained results showed that, in general, the MPD method combined with the equivalent linear analysis would produce more critical results than other methods.