Comparative Stabilization and Model Prediction of CBR Values of Orukim Residual Soils, AkwaIbom State, Nigeria

Abstract

Abstract:River sand and cement stabilization of Orukim residual soils were essentially designed to improve the engineering properties and to ascertain structural behaviour on engineering applications.The major goal of treating a residual soil is to increase the shear strength and loading capacity. The laboratory stabilization experiments involved four different soil samples from four distinct borrow pits. River sand content varied from 10% to70% and complemented by residual soil which content varied from 90% to 30% respectively. CBR results obtained ranged from 66% to 90%.Conversely cement content utilizedranged from 2% to 10% and the residual soil content varied from 98% to 90% respectively. The CBR values obtained ranged from 70% to 127%. From the results cement stabilization tends to generate optimal values of CBR as compared to river sand stabilization. The contribution of hydrated calcium silicates [C2SHx.C3S2HX] and calcium aluminates [C2AHX.C4AHX] in cement tend to increase the bonding between particulate structures resulting in plasticity reduction hence gaining in strength propagation. Finally multiple non-regressed models were developed to aid prediction and optimization of CBR parameters of Orukim residual soils at various levels of stabilization.