Effect of Volcanic Ash on Cement Stabilized Lateritic Soil: A Laboratory and Field Approach

Abstract

This research work is aimed at strengthening weak soil using volcanic ash with ordinary Portland cement for road stabilization. Standard laboratory tests were carried out on the lateritic soil which includes Specific gravity, Atterberg limits, Particle size distribution, Compaction test and California Bearing Ratio (CBR) were carried out. The soil was classified as A-7-5 soil according to AASHTO soil classification system. A 15 m section of untarred road was identified and demarcated into three sections (A, B and C) of 5.0 m each, materials on section A of the road composed of lateritic soil, 4 % cement and 2 % volcanic ash. Section B contains lateritic soil and 4 % cement while section C composed of lateritic soil only. In-situ density test and CBR test using Dynamic Cone Penetration (DCP) were carried out on the three sections of the road after 1, 7, 14, 28, 60 and 90 days. Results shows that the laboratory and field densities agreed, the laboratory and field California Bearing Ratios (CBR) differed widely.