Washington D.C., May 2, 2022 - The Portland Cement Association (PCA) applauds the three new state Departments of Transportation (DOTs) that recently approved the use of portland-limestone cement (PLC). These announcements by Maryland, Arizona and Vermont mean that a total of 44 states, many of which run comprehensive test programs to confirm concrete performance with their local materials and mix designs, now accept PLCs.
Most commonly designated as Type IL cement and produced to meet ASTM C595, Standard Specification for Blended Hydraulic Cements, PLC allows for 5% to 15% of ground, uncalcined (unfired) limestone to be blended and/or interground with clinker and other ingredients. The resultant cement offers similar performance to traditional portland cement but with a CO2 footprint up to 10% lower.
PLCs are designed for the same uses as traditional portland cements, in the same amounts in concrete mixtures – simply, using PLC is a one-to-one substitution for traditional portland cement. Other ingredients in concrete mixtures are also unchanged: the same dosage of supplementary cementitious materials (SCMs) like fly ash and slag cement can be used, as well as chemical admixtures, making adoption of Type IL cement an easy transition with simple modifications to existing specifications. Specifiers simply need to add language that allows use of ASTM C595 Type IL as an alternative to other acceptable cement types (which are most commonly ASTM C150 Type I or I/II).
Use of PLC for transportation and all other concrete applications has been steadily increasing since October 2020, when PCA formally introduced www.greenercement.com to raise awareness and educate specifiers, builders and other users about the benefits and use of this lower carbon cement. Since its introduction in the U.S., more than 6 million metric tons of PLC has been used in concrete throughout the country, and its use is growing. Widespread acceptance of PLC marks a significant step to reducing the carbon footprint of concrete construction and advancing the goals laid out in the PCA Roadmap to Carbon Neutrality.
For a map of DOTs currently accepting PLC, click here. PLC is widely available in the U.S.: for a list of PCA members’ plants and terminals providing PLC, click here.
The Portland Cement Association (PCA), founded in 1916, is the premier policy, research, education, and market intelligence organization serving America’s cement manufacturers. PCA members represent the majority of U.S. cement production capacity, having facilities across the country. The association promotes safety, sustainability, and innovation in all aspects of construction, fosters continuous improvement in cement manufacturing and distribution, promoting economic growth and sound infrastructure investment.
Nick Ferrari, Senior Vice President Communications – email@example.com