Document Type : Original Article
Dept. of Civil and Environmental Engineering, Shiraz University of Technology, Shiraz, Iran
Slope instability has been identified as one of the most frequent natural disasters that can lead to enormous monetary loss and human life in danger. Landslide initiates from one or more combinations of factors like slope geometry, slope material strength, geohydrological condition, structural discontinuity, weathering, development of weak zones, lithological disturbance, and heavy rainfall. The accuracy of parameters obtained from geotechnical investigations is vital for a practical understanding of geotechnical projects. The back analysis is an effective approach to improve knowledge on parameters controlling the landslide. In this paper, the authors present a stochastic back analysis of a recent landslide at a highway in the south of Iran. The information available from air photos, field observations, and recent photographs indicated that the observed slope failure is relatively new; boreholes were drilled in the area to investigate subsurface soil conditions. To account the uncertainties in input parameters, the stochastic back analysis approach was adopted. Soil strength parameters have been calculated using the Finite Element Method (FEM) codes program in MATLAB. Results, which agreed closely with the findings of the post-event investigations, showed a computationally more efficient back analysis approach. The improved knowledge of the geotechnical strength parameters gained through the stochastic back analysis better elucidated the slope failure mechanism, which provides a basis for a more rational selection of remedial measures.