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Slope Stability Assessment Using Drains: A PLAXIS 2D Analysis at MUET, Jamshoro

Authors

  • Faizan Ali Abro

    Department of Civil Engineering, Mehran University of Engineering and Technology, Jamshoro, Pakistan
    Author

  • Zaheer Ahmed Almani

    Department of Civil Engineering, Mehran University of Engineering and Technology, Jamshoro, Pakistan
    Author

  • Muhammad Rehan Hakro

    Department of Civil Engineering, Mehran University of Engineering and Technology, Jamshoro, Pakistan
    Author

  • Saquaib Mustafa Almani

    Department of Civil Engineering, Mehran University of Engineering and Technology, Jamshoro, Pakistan
    Author

DOI:

https://doi.org/10.22581/0608

Keywords:

Slope Stability, Rainfall, Numerical Modeling, PLAXIS-2D, Horizontal Drains, Factor of Safety (FOS)

Abstract

This research investigation evaluates the slope stability of the road that is adjacent to Mehran University of Engineering and Technology (MUET), Jamshoro's administration building. The region’s steep topography and unpredictable rainfall can lead to slope failure and damage infrastructure. To evaluate the road slope’s performance, PLAXIS-2D (finite element modelling software for geotechnical analysis) was used for precise simulations. The analysis demonstrated that even in dry weather, the slope had a relatively low Factor of Safety (FOS), i.e., 1.238, due to its steep gradient and its considerable height. The FOS further decreased to 1.002 when it was exposed to rainfall intensity of 0.06 m/day (2.5 mm/hr), which implies that it is at risk of failure. Excessive pore water pressure was found to be one of the causes of instability, and traffic loads only aggravated the situation, contributing to deformation. Horizontal drains were used to stabilize road slope. Different configurations were tested, and the best results were obtained when drains were installed at 1 m spacing across the full width and depth of the road slope, starting from its base. This arrangement successfully reduced excessive pore pressure and restored stability to a safer level. However, the FOS of 1.11 was achieved, and it is only enough to solve rainfall-induced instability; it was insufficient to address other factors that cause slope instability, such as heavy traffic loading or seismic activity. Therefore, to improve further stability, the road slope should be flattened with sandy material by obtaining from riverbeds or other sources. This approach involves removing existing ripraps, adding fresh materials to level the slope while maintaining quality control, and then reconstructing the riprap. Additionally, combining these precautions with horizontal drains has the potential to raise the factor of safety above 2, offering further protection against slope failure under many different situations.

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Author Biographies

  • Faizan Ali Abro, Department of Civil Engineering, Mehran University of Engineering and Technology, Jamshoro, Pakistan

    Post-Graduate from Geotechnical and Highway Engineering, Mehran University of Engineering and Technology, Jamshoro

  • Zaheer Ahmed Almani, Department of Civil Engineering, Mehran University of Engineering and Technology, Jamshoro, Pakistan

    Professor in Civil Engineering, Mehran University of Engineering and Technology, Jamshoro

  • Muhammad Rehan Hakro, Department of Civil Engineering, Mehran University of Engineering and Technology, Jamshoro, Pakistan

    Lecturer in Civil Engineering Department, Mehran University of Engineering and Technology, Jamshoro

  • Saquaib Mustafa Almani, Department of Civil Engineering, Mehran University of Engineering and Technology, Jamshoro, Pakistan

    Post-Graduate from Geotechnical and Highway Engineering, Mehran University of Engineering and Technology, Jamshoro

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Published

2026-04-01

Issue

Vol. 45 No. 2 (2026): April Issue

Section

Articles

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Copyright (c) 2026 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

Slope Stability Assessment Using Drains: A PLAXIS 2D Analysis at MUET, Jamshoro. (2026). Mehran University Research Journal of Engineering and Technology, 45(2), 110-121. https://doi.org/10.22581/0608

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