Effect of Selected Petroleum Products on the Geotechnical Properties of Lateritic Soil

Abstract

Petroleum contamination causes significant environmental impacts and presents substantial hazards to human health. This study was carried out to identify the effect of selected petroleum products such as petrol, diesel oil and engine oil on the geotechnical properties of lateritic soil in Ede Town (Federal Polytechnic Ede North Campus). Soil samples were collected from both the natural soil (non-oil spillage soil) and contaminated area where there were oil spillage and addition of petrol, diesel oil and engine oil in varying percentages of 5%, 10%, 15% and 20% respectively. The results showed an increase in grain size distribution on both soil samples with a reduction in optimum moisture content, maximum dry density and Atterberg limit (liquid and plastic limit) respectively. The test results showed an increase in maximum dry density with increasing oil contamination of diesel oil to 20% with reduced optimum moisture content. It was found that the maximum dry density for lateritic soil decreased as petrol content increased up to 20%. However, the reduction in the California bearing ratio due to selected petroleum products (petrol, diesel oil and engine oil) contamination, shows that the presence of these petroleum products has remarkable effect on the geotechnical properties of lateritic soil. The effect of petrol on the geotechnical properties of soil seems to be very low of 0.70grams/ml compared to that of diesel oil of about 0.832grams/ml and engine oil of about 0.875grams/ml respectively due to little time it tends to dry off. The lateritic soil is classified as an A-2-6 soil by AASHTO system and are adjudged suitable for sub grade, good fill and sub-base and base materials. But when being contaminated, the strength of the soil reduces and makes it unsuitable for road foundation design and other construction works. Therefore, lateritic soil contaminated with these petroleum products requires stabilization or an improvement technique such as the use of prefabricated vertical drains.

Keywords: Lateritic soil, Petroleum products, Contamination, Compaction, California bearing ratio (CBR)

DOI: 10.7176/CER/14-3-08

Publication date:May 31^st 2022