A safety factor of 1.5 is generally desired while planning the prevention measures against landslides. However, achieving this value may not be economically feasible in some cases, especially for developing countries with limited budgets. Landslide along the 62 km of Charali-Ilam Road in Nepal was stabilized with a designed factor of safety of 1.2. The post construction monitoring of the landslide showed that the landslide has been completely stabilized with the designed prevention work. However, there was a concern for this landslide during the recent Mw 6.9 Indo-Nepal Board Earthquake as the expected factor of safety for the estimated seismic acceleration was close to 0.8. The landslide performed well during the seismic event due to the increase in strength by healing. This shows that for highly plastic clays where shear strength can potentially increase with healing, prevention planning can be done with a lower factor of safety if the stability analysis is done with back analysis method, ignoring the cohesion.
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