Waste paint as an admixture in concrete

A significant volume of waste latex paint exists in New Zealand, with the rate of supply rapidly growing, prompting an investigation into the use of waste paint as a polymeric admixture in concrete due to similarities in chemical compositions of waste paint and polymeric admixtures. The objective of this study was to produce a blockfill mix capable of maintaining or improving the properties of the hardened material whilst increasing the efficiency of the construction process. The optimum dosage to achieve the required strength and workability was found to be approximately 12% replacement of mix water with waste paint, while the Modulus of Elasticity was found to be a function of compressive strength. Rheological testing indicated that regardless of paint concentration, the yield stress of the blockfill increased whilst the viscosity and separation rate decreased. It was established that waste latex paint was a suitable replacement for conventional admixtures in concrete masonry blockfill, resulting in maintained strength and improved workability.