Analytical and Numerical Study of the Stability of Trench Slopes (Case Study: The Trench Adjacent to the Yasouj University Library)

Document Type : Original Article

Authors
1 M.Sc., Student, Department of Civil Engineering, Faculty of Engineering, Yasouj University, Yasouj, Iran.
2 Assistant Professor, Department of Civil Engineering, Faculty of Engineering, Yasouj University, Yasouj, Iran.
Abstract
Determining the geometry of the rupture surface is considered to be one of the most effective steps to accurately determine the safety factor of slope stability. In most of the analysis, for ease of calculations, the rupture surface is assumed to be linear or circular, which sometimes does not correspond to reality. According to the observation of ruptures in the trench adjacent to the central library of Yasouj University, the present research has investigated local ruptures in the domain. By surveying the studied trench and collecting geotechnical information, for seven sections of this trench, with the rupture surface and circular surface with Bishop's method, in the SLOPE/W and with the -c reduction method was analyzed in PLAXIS software and results were compared. Bishop's method predicted rupture wedges with a circular surface for trench, which was contrary to actual rupture surface formed. By analyzing the trench in PLAXIS 3D, the rupture wedge was obtained in a way different from reality with safety factor less than 1. Based on the analysis, it was found that analytical and numerical models were not able to correctly predict the geometry of the rupture surface and the safety factor. The rupture surface occurred in the current slope did not conform to the numerical and analytical models. Therefore, by using the spline interpolation method in MATLAB for each section of the trench, the curve and the equation of its failure procedure were obtained, which stability analysis on these surfaces provides more realistic of slope stability safety factor.
Keywords

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