Effect of Oil Contamination on Lime Stabilized Soil

This study was carried out to evaluate the effect of spent oil contamination on the strength of lime stabilized soil. Laterite soil was stabilized with lime in percentages of 0, 2, 4, 6, and 8% of the dry weight of soil. Specimens were prepared for UCS and CBR. The specimens for UCS were cured for 7, 14 and 28 days; while the specimens for CBR were cured for 4 days. Contamination of the specimens was achieved by soaking in spent oil medium in a plastic bowl for 48 hours after the respective curing periods. The uncontaminated soil and the contaminated soil were both tested for UCS and CBR. The results obtained show that the strength of lime stabilized soil decreased when contaminated with oil. The value of the UCS decreased by about 46, 23 and 13% on the average for soil-lime mixture cured for 7, 14 and 28 days, respectively. Similarly, the CBR of the soil-lime mixture reduced by about 35%. It was also observed that the resistance to loss in strength increased with lime content and curing period. This results show for all practical purposes that a lime stabilized pavement structure exposed to oil contamination is susceptible to failure as a result of reduction in strength and bearing capacity due to oil contamination.