Effects of seismic amplification on the 3D stability of fill slopes in V-shaped valleys.

Seismic amplification effects are a common occurrence in V-shaped valleys. A method is presented for incorporating the amplification effects in the stability assessment of V-shaped fill slopes based on the limit equilibrium (LE) method coupled with the pseudo-static approach. The proposed LE method uses a variationally derived three-dimensional (3D) rotational failure mechanism to produce stability charts for slopes. A series of parameter analyses are conducted to investigate the influences of seismic load and the geometric parameters on the 3D stability and the most critical slip surface for V-shaped fill slopes. The findings indicate that the reduction in the slope stability triggered by the seismic amplification effects is notable. The boundary effects are positively correlated with the inclination of the valley side slope and negatively correlated with the width of the valley bottom. The face failure mode is dominated in the cases where the boundary effects are significant. Furthermore, an explicit expression equation of the safety factor, the stability equation, is obtained by regression analysis. This stability equation has excellent accuracy and can be used in practical engineering to provide a convenient assessment for V-shaped fill slopes. [ABSTRACT FROM AUTHOR]