Agronomical Stabilization of Umuda-Isingwu Erosion Site Using Vetiver Grass
Keywords:Soil erosion, embankment stability, Vetiver grass, factor of safety
Soil erosion and embankment failures are serious challenges confronting our environment. In the face of these challenges, different possible solutions are been studied at different levels with special consideration on the implementation cost of such solutions. Hence, this work studied agronomical stabilization of Umuda- Isingwu erosion site using vetiver grass. The principal objective of this study was to determine the stability of an engineered slope by computing the factor of safety (FS) of the samples collected from the embankment on the erosion site. To ascertain the factor of safety, the soil samples collected from the study area were analyzed to determine its gradation by mechanical sieving and hydrometer method, while the density bottle was used to estimate the density of the samples which when multiplied by acceleration due to gravity of 9.81m/s2 gave the unit weight of samples. The results showed that the soil samples are coarse sand and loamy sand, unit weight of bare and Vetiver rooted samples as 17.40KN/m3 and 16.62KN/m3 respectively, average shear strength of the bare soil samples and Vetiver rooted soil samples as 68.52KN/m2 and 132.32KN/m2 respectively and the factor of safety of the samples; bare and Vetiver rooted soils were computed to be 1.72 and 2.98 respectively. These computed factors of safety showed that Vetiver rooted samples are about 1.73 times more stable than the bare soil. Hence, Vetiver grass is a good embankment and erosion site stabilizer and should be put to effective use in the area erosion control and slope stabilization in Nigeria.
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