A research partnership between Oak Ridge National Laboratory (ORNL) and the University of Tennessee has led to the development of a quick-setting concrete mix that is expected to reduce manufacturing time in the precast industry.

The concrete mix demonstrated high early strength within six hours of mixing, potentially doubling the production capacity for the precast industry, according to ORNL. The researchers used commercially available components including steel, glass and carbon fibres in the study, resulting in a self-compacting fibre-reinforced concrete mix that not only exhibited early strength but also maintained its workability for 30 minutes.

Quick performing concrete shortens manufacturing turnaround for prefabricated assemblies such as walls, beams and floor slabs. However, such concrete mixes showing early strength have short setting times and, therefore, require specific curing methods.

"We followed a practical, cost-effective process easily implemented with typical mixing procedures," ORNL's Diana Hun said. "This could enable precast plants to cast twice per day."

Future areas of study include reducing the amount of carbon embodied in the mix.

The study was conducted in collaboration with the Precast/Prestressed Concrete Institute.