Stability analysis of the cut slopes in the locality of Limbe using numerical modeling (South-West Cameroon)

The aim of this work has focused on the stability analysis of the cut slopes in the locality of Limbe using numerical modeling in order to produce susceptibility models and solutions against landslide-prone soils. Field and laboratory work have been carried out. Four slopes were analyzed and simplified slope models were then generated using Bishop’s approach to slope/w analysis in the Geostudio software. The studied materials have high mean natural water content (37.18%), are very porous (63.51%), and are plastic (29.6%). Consequently, they are very sensitive to creep. Moreover, the cohesion of these materials ranged between 0.283 to 1.15 bars while a friction angle falls between 19 and 41.5°. Furthermore, a safety factor of 0.831, 0.307, and 0.961, which are less than 1, was obtained for the Mbonjo1, Mbende uphill, and Moliwe sites, respectively, hence their unstable character. Stabilization techniques were then tested on the slopes in order to improve the safety factor values. Among the stabilization techniques selected, the best was load surcharge on the slopes which increased the safety factor values from 1.3, 1.725, and 1.704, respectively. However, a Livanda Congo slope is stable with a safety factor of 2.02.