A PARAMETRIC STUDY OF SLOPE STABILITY ANALYSIS IN COHESIVE SOILS USING A PROBABILISTIC METHOD

  • AHMED J. HAJI *Civil Engineering Department, College of Engineering, University of Duhok, 1006 AJ Duhok, Kurdistan Region-Iraq
  • MOHAMMED S. HUSSAIN **Civil Engineering Department, College of Engineering, University of Duhok, 1006 AJ Duhok, Kurdistan Region-Iraq

Abstract

The probabilistic analysis of slope stability, accounting for the heterogeneity of the soil medium, was attempted in this study using an advanced approach called the Random Finite Element Method (RFEM). The method was used to investigate the effects of two statistical parameters, namely the coefficient of variation (CoV) and the isotropic spatial correlation length (θ = θx= θy) of different soil parameters on the probability of failure (Pf) of a cohesive soil slope. The statistical effects of cohesion (C), angle of internal friction (Φ), modulus of elasticity (E), and unit weight (ɣ) of the 5V:6H soil slope were examined. The investigated values of θ were 1, 5, 10, 20, 30, and 50 m. The considered CoV values of cohesion (CoVC) were 0, 0.1, 0.2, 0.3, 0.4, 0.5, and 0.7 and the CoV values of Φ (CoVΦ) were 0, 0.05, 0.10, 0.15, 0.20, and 0.30. It is highlighted that the correlation length was directly proportional to the Pf for all the implemented parameters. Moreover, the results show that higher values of CoV of all the parameters corresponded to higher Pfs. Notably, changes in the CoVC and CoVΦ had a more significant impact on failure probability compared to variations in the modulus of elasticity or unit weight.  For the cases with high correlation length and large CoVC, a measured failure probability of about 45% was noted. In terms of uncertainty of Φ, the slope with large CoVΦ experienced the Pf varying from 20% to 40% at the larger values of θ. Finally, the study brought attention to the significance of considering the spatial variability of soil properties for conservative evaluation of the stability of soil slopes.

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Published
2024-10-08
How to Cite
HAJI, A. J., & HUSSAIN, M. S. (2024). A PARAMETRIC STUDY OF SLOPE STABILITY ANALYSIS IN COHESIVE SOILS USING A PROBABILISTIC METHOD. Journal of Duhok University, 27(1), 16-29. Retrieved from https://journal.uod.ac/index.php/uodjournal/article/view/3363
Section
Pure and Engineering Sciences