Stabilization of A-6 Lateritic Soil Using Rice Husk Ash and Promoter

Abstract

Lateritic soil sample classified as A-6, taken from a borrow pit at Birgin Gwari, Minna, was stabilized with 0 to 6% Rice Husk Ash (RHA), at 2% variations. Each of the soil-RHA mixture was admixed with 0 to 2% promoter (calcium chloride and sodium hydroxide), at 0.5% variations. Unconfined Compressive Strength (UCS) test samples of the soil-RHA-promoter mixtures were prepared at Maximum Dry Density (MDD) and Optimum Moisture Content (OMC), cured for 1, 7, 14, 28 and 60 days, before testing. The results indicated marginal increase in UCS with increase in curing period, but no defined trend in the UCS values was observed as curing period increases constant promoter content. The results also indicated that, at constant percentage content of promoter, increase in percentage of RHA has more pronounced effect on the strength (UCS) of the stabilized soil than curing age. The UCS values peak at 6% RHA/0.0% promoter and 28 days curing period.