Stabilization of Lateritic Soil with Binary Stabilizer Activated With Calcium Chloride for Highway Pavement Construction
Osuolale, O. M., Oluremi, J. R. and Olaniyan, K. D.
Department of Civil Engineering, Ladoke Akintola University of Technology, Ogbomoso, Nigeria
DOI: 10.36108/laujoces/5202.51.0180
Abstract
Lateritic soil is one of the most common materials for highway pavement construction in Nigeria. However, due to its poor geotechnical properties and the contribution of conventional stabilizers like cement, lime and bitumen to environmental pollution, there’s a need to investigate other materials that are eco-friendly and pozzolanic enough to effectively stabilize lateritic soils. This study investigated the effectiveness of Sawdust Ash (SDA) and Steel Slag (SS) activated with calcium chloride on the stabilization of lateritic soil. Geotechnical properties: Liquid Limit (LL), Plastic Limit (PL), Plasticity Index (PI), Maximum dry Density (MDD), Optimum Moisture Content (OMC), Unconfined Compressive Strength (UCS) and California Bearing Ratio (CBR) were determined for the lateritic soil sample collected from a borrow pit in Ogbomoso, Nigeria before and after mixing it with varying proportions of SDA, SS and CaCl2. The LL, PI, and OMC of the soil reduced after admixing it with SDA, SS and CaCl2, with corresponding increase in MDD, UCS and CBR, an indication of improvement in the geotechnical properties. The mix proportion of 81.5% Soil, 10% SDA, 8% SS and 0.5% CaCl2 produced the highest CBR and MDD values of 95% and 1.88 g/cm3 and the lowest PI value of 4%. The use of ternary admixture of SS, SDA and CaCl2 for the stabilization of lateritic soil proved effective towards sustainability and therefore recommended for stabilization of the same for use in highway construction.
Keywords: Lateritic Soil, Sawdust Ash, Steel Slag, Calcium Chloride, Geotechnical Properties, Optimization