Numerical analysis of slopes stability under seismic loading in Lebanon

Most common methods used in engineering practice to assess the seismic stability of slope consists of a pseudo static approach or traditional approaches based on the limit equilibrium or on the hypothesis of failure calculation. Such methods are widely used because of their simplicity and there is no need of sophisticated software for their application. However, they neglect important elements such as the soil deformability, the dynamic amplification and non linear soil behavior. The present study concerns the analysis of the seismic slopes stability using global dynamic approach. It will mainly focus on dynamic amplification in the slope under real earthquake records with frequency content close to the natural frequency of the slope. Analysis is conducted by numerical modeling using Flac3D finite difference program. Results are presented in the case of linear visco-elastic then elastoplastic behaviour for earthfill materials in order to elucidate the influence of plasticity.