Page - 974 - in Book of Full Papers - Symposium Hydro Engineering

COMMISSION INTERNATIONALE DES GRANDS BARRAGES ------- VINGT-SIXIÈME CONGRÈS DES GRANDS BARRAGES Autriche, juillet 2018 ------- VEGETATION EFFECT ON RELIABILITY ANALYSIS OF SLOPE STABILITY USING MONTE CARLO SIMULATION Iman VAEZI1, 4, Hesam SAEIDI2, Ali NOOZAD3, 4 1. Geotechnical Engineer, PEY AB AZMA CONSULTING ENGINEERS 2. Data analyst, PEY AB AZMA CONSULTING ENGINEERS 3. Faculty member, Faculty of Civil, Water and Environmental Engineering, SHAHID BEHESHTI UNIVERSITY 4. IRANIAN COMMITTEE ON LARGE DAMS IRAN 1. INTRODUCTION The necessity of dam construction is prima facie principle in arid or semiarid regions. As an inevitable consequence in dam construction, unnatural slopes around dam body and reservoir are formed and usually devoid of vegetation. Failures of those slopes can have a significant cost. Translational failure is defined as linear movement along a bedding plane or a soil layer lying near to the surface. Such movements are normally fairly shallow and parallel to the surface [1]. Vegetation surely affects hydrological and mechanical properties of slopes related to slope stability and shallow landslide triggering. The most important and general problem is a shallow seated instability of a slope [2]. Based on the complexity of soil-plant mechanical interactions, the quantification of root mechanical reinforcement remains a challenge. On the other hand, considering the failure mode and uncertainty in geotechnical and vegetation parameters, it seems that using probability theory in slope analysis is inescapable. The aim of this study is evaluation of increased shallow landslide resistance of a slope due to vegetation considering uncertainty of related parameters. With reliability analysis it is possible to quantify the uncertainties involved in the problem and to determine safety factor according to the degree of uncertainty and acceptable risk. 974