Portland-limestone cement reaches universal state DOT approval

The Florida Department of Transportation approved ready mixed concrete with an Argos USA Type IL cement for pier and other cast-in-place structures on the Bayway Bridge (above) and a companion Gateway Expressway structure (below), both part of the four-lane S.R. 690 toll road under way in Pinellas County.

Portland Cement Association reports across the board state agency approval of portland-limestone cement, or ASTM C595 Type IL binder, on the heels of a Connecticut Department of Transportation green light for the material. Compared to ASTM C150 Type I/II portland cement, PLC is finished with higher limestone content, while exhibiting a carbon dioxide emissions footprint up to 10 percent lower. PCA estimates that in 2023, U.S. cement producers avoided emitting more than 4 million metric tons of CO2 by incorporating PLC and other blended cement alternatives. The 50-state plus District of Columbia Type IL approval milestone arrives as transportation agencies—key cement and concrete users in the overall public construction arena—are stepping up consumption as Infrastructure Investment and Jobs Act funding drives higher than normal levels of road and bridge work.

PHOTOS: PCA/Greenercement.com

“This is a huge step for sustainable American construction,” says PCA CEO Mike Ireland. “Using a lower-emission product that meets all the performance requirements of traditional cement means the construction sector can build with durability, safety and sustainability in mind.”

The Connecticut DOT move caps cement producers’ rapid shift from Type I/ll portland to Type IL blended cement output, driven by market factors and adoption of the PCA Roadmap to Carbon Neutrality, released in late 2021. PLC production and acceptance are among the document’s near-term CO2 reduction measures as PCA members and downstream construction parties approach 2050, the target for the industry to operate as carbon neutral. Recent U.S. Geological Survey data reveals that the U.S. market share for PLC surpassed that of traditional portland cement in June 2023.