Slope Stabilization through Bioengineering with Vetiver Grass: Impact on Bearing Capacity, Erosion, and Runoff

Landslides, aggravated by natural and human factors, generate risks, economic losses, and affect the safety of vulnerable populations. In this context, the research focuses on evaluating the use of vetiver grass as a sustainable and ecological solution for slope stabilisation. The methodology included the geotechnical characterisation of the soil in the central jungle of Peru (San Pedro sector, Tarma-La Merced section) located at UTM coordinates Zone 18L: 481098.70 m E and 8790688.01 m S, where modified Proctor was applied and, with these parameters, 35 wooden prototypes measuring 50 × 50 × 80 cm were compacted in three layers, forming slopes of 20°, 25°, 27.6°, 30° and 35°. Vetiver grass was planted on them at densities of 10, 15, and 20 cm. The models were evaluated by means of direct shear, erosion, and runoff tests under simulated rainfall of 47.7 mm/h, at 21 and 30 days, comparing them with slopes without vegetation cover. Vetiver grass significantly improved slope stability, increasing soil cohesion by 60%, the angle of friction by 12% and bearing capacity by 53% on 20° slopes. In addition, it reduced erosion by up to 92% and surface runoff by up to 37%. The planting density of 15 cm showed the best performance, consolidating vetiver as an effective and sustainable alternative for slope stabilisation. The research contributes to the field of geotechnics, demonstrating that vetiver grass is a sustainable solution for stabilising slopes by improving soil resistance and reducing erosion and runoff.