Use of quick and hydrated lime in stabilization of lateritic soil: comparative analysis of laboratory data

A laboratory study was undertaken to evaluate and compare the stabilization effectiveness of different percentages (0, 2.5, 5, 7.5, 10%) of quick and hydrated lime when applied separately to locally available lateritic soil, a major soil group in the tropical and sub tropical regions. Performance evaluation experiments included: Atterberg limits, compaction, unconfined compression tests, California bearing ratio (CBR), swelling potential using CBR instrument and hydraulic conductivity. The soil mixtures used for unconfined compressive strength (UCS), CBR, swelling potential and hydraulic conductivity tests were compacted at optimum moisture content using the British standard light compactive effort and cured for 28 days. It was found that the quicklime caused the soil to have lower plasticity while hydrated lime yielded higher dry unit weight. Also, higher UCS especially at higher dosages ( 7.5 and 10%) was produced when soil sample was treated with quicklime. Similarly, the CBR values for quicklime sample clearly indicate that quicklime-stabilized soil have superior load bearing capacity. Finally, quicklime treated specimens reached slightly lower swelling values than the hydrated lime while no appreciable distinction in hydraulic conductivity values of specimens treated with the two types of lime was observed. From the foregoing results, quicklime is adjudged to have exhibited somewhat superior engineering properties and therefore creates a more effective stabilization alternative for the soil.