Evaluation of the Biomechanical Potential of Pennisetum Purpureum and Mangifera Indica Plant Roots for Sustainable Slope Stabilization

Abstract

Abstract: The potentials of the roots of Pennisetum purpureum and Mangifera indica for use in sustainable stabilization of slope were evaluted. The plant roots were sampled close to an erosion site in Nwonta Isuikwuato local government of Abia State Nigeria. The tensile strength of the roots segments was determined using the Universal Testing Machine (UTM) at the Michael Okpara University of Agriculture, Umudike. The effect of water content and dehydration due to adverse weather condition was studied by tensile testing the roots after different drying periods (30 minutes, 1 hour, and 24 hours). Laboratory experiments was performed to evaluate the engineering properties of the soil at the erosion site. The mean tensile strength of the Pennisetum purpureum obtained were 5.30 MPa (hydrated roots), 12.49 MPa (30 minutes dried) and 17.13 MPa (1 hour dried). After 24 hours drying the roots of Pennisetum purpureum which is a grass species was not strong enough to be tested for tensile strength. For the Mangifera indica the mean tensile strength obtained were 17.41 MPa (hydrated roots), 18.73 MPa (30 minutes dried) and 21.84 MPa (1 hour dried) and 34.10 (24 hours dried). The roots show that root tensile strength increased as the root moisture content reduces. The heightened rate of soil erosion in the study area could be due to the fact that the soils are predominantly sand with no cohesion as observed from the laboratory test. Hence, planting these vegetations can significantly lead to the improvement of the strength properties of the soil and minimise the rate of soil erosion and slope failure.