Effects of adding Kuwaiti oil-contaminated sand as a fine aggregate substitute on the engineering properties of hardened concrete

A laboratory scale study was undertaken to investigate the potential use of Kuwaiti oil-contaminated sand, as a substitute for fine aggregate in hardened concrete and its effect on its engineering properties. The average concentrations of Total Petroleum Hydrocarbons (TPH) for contaminated and treated specimens were 50,000 and 10,000 mg/kg, respectively. An experimental evaluation of the concrete mixture's workability was conducted using British standard methods. The results of this investigation indicated that the designed concrete cubes with contaminated sand require special attention with regard to the mixing ratio, which was found to be 1:1.5:3 (cement:fine aggregate:coarse aggregate) at 0.48 w/c. All workability tests were conducted on concrete cubes made from uncontaminated sand and sand with TPHcontamination ofless than 10,000 mg/kg, which are lowered than the upper limits (TPH <10,000 mg/kg) of Kuwait Environmental Protection Agency (KEPA). The results indicate that the presence of oil contamination did not have any adverse effect on the compressive strength of the concrete while water absorption was enhanced by the oil-contaminated sand to about three times that of the control. This investigation points to the potential for green building technological applications using oil-contaminated sand, which if left unattended, is likely to cause environmental harm.