It was investigated how COIS (crude oil impacted sand) affected the compressive strength of concrete. All specimens with a w/c of 0.5 were intended to use the concrete mix, 1:1.8:2.7. Sand was contaminated with crude oil (2.5%, 5%, 10%, 15%, 20%, and 25%) by weight in order to create COIS concrete. Concrete cubes measuring 147 100 mm were made (with 21 control samples and 126 contaminated samples). The compressive strengths of the cubes were assessed at ages 3, 7, 14, 28, 56, 84, and 168 days after curing. In comparison to the control samples, the COIS concrete samples exhibited a slow rate of strength gain and a drop in strength. A loss of 18–90% compressive strength was experienced as a result of 2.5–25% crude oil contamination.

Impact of Sand, Contaminated with Crude Oil, Concrete's Engineering Properties.