EFFECT OF ORGANIC CONTAMINANT ON SHRINKAGE PROPERTIES OF LATERITIC SOIL

Abstract

ABSTRACT Contamination modifies the engineering properties of soil, thereby restricting its further use either as s construction material or as a supporting medium. Due to the scarcity of land, it becomes imperative to reuse such areas for infrastructure developmental activities. The objective of this study is to determine the effect of organic contaminants on shrinkage properties of lateritic soil. Out of numerous soil contaminants, benzene was chosen in this study. Three lateritic soil samples were collected from Gidan Kwano campus of Federal university of Technology, Minna. Each sample was contaminated with varying percentage of benzene 2.5, 5, 7.5, and 10% wrapped in the polythene bag for 48 hours. Performance was evaluated on Atterberg limit, Compaction characteristic and shrinkage properties of contaminated soil. Soil specimens for shrinkage tests were compacted with British Standard Light (BSL) compactive effort at predetermined optimum moisture content. Result of the Atterberg limit tests show that, plasticity of the contaminated soil samples were increased as the degree of benzene used increased. Result of compaction tests show that the dry unit weight of soil samples were slightly lowered on contamination. The optimum moisture content increased marginally with increase in benzene concentration. Finally, as the percentage of benzene used increased, it was observed that the volumetric shrinkage increased with number of days. For example, volumetric shrinkage at 2.5% were 8.4, 8.5 and 9.1 respectively while that of 10% were 38.84, 38.87, and 46.91 respect