Effect of Plantain Peel Ash on the Strength Properties of Tropical Red Soil
Authors: Ishola K, Olawuyi OA, Bello AA, Yohanna P
The effect of plantain peel ash (PPA) on the strength properties of tropical red soil was studied. Natural soil was classified as Lean clay (CL) according to the Unified soil classification system or A-7-5 according to American Association of State Highway and Transportation Officials classification. Test method employed involved treating lateritic soil with plantain peel ash in concentration of 0, 2, 4, 6, 8 and 10% PPA by dry weight of soil. Test carried out include specific gravity, consistency tests, compaction test using British standard light (BSL), unconfined compression test (UCS) and California bearing ratio (CBR). Analysis of variance was carried out using Microsoft Office excel analysis tool pack. Test results shows that specific gravity initially decreased and thereafter increased with higher PPA content. Liquid limit, plastic limit, plasticity index and linear shrinkage decreased with higher PPA content. Maximum dry density (MDD) values increased while optimum moisture content (OMC) decreased. UCS increased from its natural value of 172.8 kN/m2 to peak value of 286.9 kN/m2 at 10% PPA content. CBR (unsoaked) increased from its natural value of 65.30% to 75% at 4 % PPA content and thereafter decreased to 22.6% at 10% PPA content. The PPA treated soil did not meet the criteria specified for use as base course material by the Nigerian general specification, however, PPA treated lateritic soil at 4% PPA content can be used as subgrade material in admixture stabilization with a more potent industrially made stabilizer (i.e., cement or lime) in order to lessen cost of road construction.
Affiliations: Department of Civil Engineering, Osun State University, Osogbo, Osun State, Nigeria.
Keywords: Analysis Of Variance, California Bearing Ratio, Lateritic Soil, Plantain Peel Ash, Unconfined Compression Strength
Published date: 2019/06/30