Abstract
A large landslide has occurred causing extend soil mass instabilities, along side the East-West motorway El Harrouch section, located in Ain Bouzian commune, Skikda province within Northeastern Algeria. In this paper a probabilistic study was performed for a slope profile with a total height of 36 m. In order to assess the effect of saturation conditions on the slope stability two hydrology cases are considered with and without water table. The analysis was conducted assuming long-term conditions; therefore the effective stresses and soil properties were adopted. First a determinist analysis was done using limit equilibrium and strength reduction methods. Then in order to investigate the failure probability of the slope, the Monte Carlo Simulation (MCS) was employed. The input random variables considered in this analysis are the Cohesion C’ and friction angle φ’, with factor of safety (FOS) is the probabilistic system responses. In addition, a parametric study was carried out to inspect the effect of input geotechnical parameter variations on the reliability of slope stability.