May 19, 2015

Caltrans has completed a specification that allows use of returned plastic concrete in minor concrete applications. The specification is the result of a long work effort between Caltrans and industry. It will allow use of up to 15% returned plastic concrete on sidewalks, curbs, and slurry backfill. It was spurred by a finding that there is a 15.3% reduction in carbon footprint and an 16.2% reduction in embodied energy from using up to 15% returned concrete compared to new mixes. It is believed to be the first such specification in the country for a state department of transportation. It will be issued as a non-standard special provision (NSSP) in Section 90-9 of the Caltrans specifications. Users of returned plastic concrete will need to get an addendum approved to their Material Plant Quality Plan (MPQP). Caltrans will send the new specification to District Office Engineers for inclusion in projects. The specification is the result of work by several members of CalCIMA’s Technical Committee, including Don Vivant (Sully-Miller), Mike Donovan (Central Concrete), Pat Imhoff (CalPortland), Tarek Kahn (BASF), and Mark Hill (CEMEX).