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Numerical Modelling of Factors Critical to Slope Stability with Plaxis 2D

Authors

  • Muhammad Rehan Hakro

    Department of Civil Engineering Mehran University of Engineering & Technology, Sindh Pakistan
    Author

  • Imtiaz Ali Hakro

    Institute of Petroleum & Natural Gas Engineering Mehran UET Jamshoro
    Author

  • Rabia Soomro

    Department of Civil Engineering, Mehran University of Engineering and Technology Shaheed Zulfiqar Ali Bhutto Campus, Khairpur Mir's, Sindh, Pakistan.
    Author

  • Faisal Ahmed Rajper

    Executive Engineer, Irrigation Department Government of Sindh
    Author

  • Shehnaz Hakro

    PhD Scholar Center for Environmental Sciences, University of Sindh Jamshoro
    Author

DOI:

https://doi.org/10.22581/muet1982.0377

Keywords:

Slope, Critical Factors, Rainfall, Loading, Piles, Factor of safety (FOS)

Abstract

Slope instability is among the primary issues in geotechnical engineering that can result in loss of life and property. This study assessed slope stability by Factor of Safety (FOS) in FEM Plaxis 2D software with different geotechnical and hydrological conditions. The Mohr–Coulomb model is used to predict behaviour of soil and the input parameters determined in the laboratory. Mohr-Coulomb constitutive model is typically more preferred than the Drucker Prager model for slope stability analysis since the soil strength is a key factor controlling slope stability. To determine the geotechnical parameters of soil samples were obtained from each slope segment. In the laboratory, soil samples were evaluated for their strength properties, soil type, size distribution, permeability, etc. The factor of safety (FOS) is determined based on various factors that contribute to slope instability. The parameters for each slope are changed, and the safety factor is determined for each step. The FOS was 2 at the load of 25 kPa and reduced to 1.4 with load of 100 kPa soil. The effect of the footing distance to the edge of the slope is represented by w/x. As the ratio decreased, an increase in the factor of safety value was observed. The FOS decreased from 2.38 to 1.76 with a rainfall duration of 20 days. This study shows that rainfall significantly reduces matric suction in soils at shallow depths, leading to a decrease in shear strength and an increased risk of shallow failures. Additionally, a non-linear relationship between setback distance and FOS was observed, emphasizing the importance of conservative design practices. Finally, the study confirms that pile installation significantly enhances slope stability, with longer piles generally leading to higher FOS. However, optimal pile length and location are highly dependent on site-specific conditions.

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References

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Published

2025-10-28

Issue

Vol. 44 No. 4 (2025): October Issue

Section

Articles

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Copyright (c) 2025 Mehran University Research Journal of Engineering and Technology

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This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

How to Cite

Numerical Modelling of Factors Critical to Slope Stability with Plaxis 2D. (2025). Mehran University Research Journal of Engineering and Technology, 44(4), 143-150. https://doi.org/10.22581/muet1982.0377

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