Abstract:
PaintWise is a nationwide paint recovery program which is based upon the recognition that waste paint is a valuable resource that is currently being disposed of in landfills at a significant economic and environmental cost. In order to utilize the beneficial properties of this waste paint as an active ingredient to produce concrete, a PaintCrete Partnership involving 3R Group Ltd, Fletcher Concrete and Infrastructure Ltd, and Resene Paints was formed. 3R Group is responsible for managing and implementing the PaintWise program, and in 2009 the 3R Group diverted away from landfill and processed over 160,000 litres of waste paint. Waste paint exhibits many desirable properties that are similar to particularly expensive polymeric admixtures, which have been commonly used in the modification of cementitious applications for well over 70 years. These properties include improved rheology, strength, toughness and durability. These improvements are due to the polymer resins found in paint exhibiting similar advantages to polymers found in conventional polymeric admixtures. An investigation was performed to identify the suitability of waste paint as a polymeric admixture substitute to improve the fresh and hardened properties of concrete mixes. A considerable amount of commercial emphasis is placed on the research methodology, with a range of different ongoing commercial applications monitored via testing of both fresh and hardened concrete, while analyzing and modifying the concrete mix designs and production procedure as required, achieving desired performance characteristics. Lab-based trials were also undertaken in order to identify mixes with the potential to be trialed at commercial levels. Previous PaintCrete Partnership research into block-fill grout was not commercialized as insufficient fullscale trials were conducted, whereas the commercial emphasis of this investigation will be of assistance in producing the end result which is fully commercialized PaintCrete; a superior concrete solution which provides enhanced job-site productivity, improved strength and durability, and which is also good for our environment.