Mechanical Properties of Ultra High Performance Fiber Reinforced Concrete Made with Foundry Sand

The ferrous and non-ferrous foundry industry produces approximately 6 million tons of foundry sand (FS) waste annually in the United States and estimates have shown that only 15% of the waste is being recycled. This study utilized FS waste in the production of Ultra High Strength Concrete (UHSC) as a partial replacement for natural sand. Natural sand was replaced with FS at the replacement levels of 0%, 10%, 20%, and 30% by volume. UHSC mixtures produced were tested to determine the compressive strength, splitting tensile strength, flexural strength, elastic modulus, and Poisson's ratio at 7, 14, and 28 days. The results showed an increase in mechanical performance up to 10% FS replacement. The results also indicate an insignificant decrease in mechanical performance at 20% replacement levels. FS had no significant impact on the Poisson's ratio of UHSC.