ABSTRACT

 The increased in crude oil exploitation in the offshore area definitely leaves huge quantity of contaminated soil. When soil is contaminated it stop being ideal for engineering works. This study gave empirical evidence on the effect of crude oil pollution on the engineering properties of concrete materials and the possibility ofits re-use for civil engineering works. Contaminated soil sample was collected from kolmani oil well in Bauchi state and laboratory analysis earned out to evaluate its engineering properties. Some soil sample were taken to chemistry laboratory to reduce the percentage contamination between 5% to 20% contamination, for this analysis. Typel ordinary Portland cement that conforms to BS12 specifications was used as binding agent while water aided the hydration and curing. Coarse aggregate of 20mm size was used and fine aggregate was acquired and used to run control test, using the British method of concrete mix design. Mix ratio of 1:1.8:2.7 at a water-cement ratio of0.5 was used for all mixes. Slump test result showsthat, at increase ofcontamination, slump increases indicating that slightly polluted soil has good workability and can serve as plasticizer in concrete. The compressive strength test shows that 20% contamination gives high strength of 16.74 (N/mm2) due to the presence of C-S-llCASH compound in the contaminated soil as seen from the scanning electronic microscopic test. This shows that contaminated soil can serve as admixture in concrete. The benefit derived from this work would enhance production ofsustainable concrete works.