Stabilization of Laterite Soil for Unpaved Roads Using Molasses in Butere and Mumias Sub Counties

Abstract

The gravel wearing course used on the unpaved roads within the area covering the sub counties of Butere and Mumias wears out too fast. This makes the roads to be in such a bad state as rutting and potholes develop hence making the re-graveling to be done frequently. This study analyzed processes involved in the stabilization of laterite gravel soil with cane molasses. The main objective was to establish the feasibility of using sugarcane molasses in stabilizing laterite soils for gravel wearing course on unpaved roads in Butere and Mumias counties. Other objectives were; to determine the physical, mechanical and chemical properties of laterite gravel soil used on unpaved roads in Butere and Mumias counties, to establish the chemical properties of sugarcane molasses used to stabilize the laterite gravel soil for unpaved roads and to determine the optimum performance of laterite gravel soil stabilized with sugarcane molasses for unpaved roads. Molasses was used in this study because it contained some elements/compounds which are known to react with laterite soil and change characteristics of the soil. Tests were carried out to determine the chemical composition of molasses and those of laterite gravel. It was evident that 2% cane molasses by weight of dry soil was the optimum for effective stabilization of lateritic soil. The study established that neat laterite soil specimens gave lower California Bearing Ratio values than one mixed with cane molasses. The increase in California Bearing Ratio values for laterite soil mixed with cane molasses higher than those of neat laterite soil was an indication that cane molasses caused the strength of the soil to increase and therefore it stabilized laterite soil. Sugarcane molasses improved the engineering qualities of the soil i.e. California Bearing Ratio values and the density and decreased the Optimum Moisture Content and Plasticity Index of soil.