The Fall 2023 newsletter of the National Concrete Consortium includes the following items:
• PEM Evolution: Then and Now: The Fall 2023 NC² Moving Advancements into Practice (MAP) Brief from the NC² Resource Library provides a background on the Performance-Engineered Mixtures (PEM) initiative; outlines the accomplishments, key findings and implementation of TPF-5(368); and provides a look at what is current with PEM regarding construction practices.
• Optimizing Concrete Pavement Opening to Traffic: This technical summary reviews current practices used to open new pavement surfaces to traffic and how opening to traffic can be accelerated when necessary. The topics covered in this technical summary include planning and contracting considerations, pavement strength development, traffic loading, pavement stresses, early-age concrete pavement fatigue damage, and materials and construction considerations for early opening of concrete pavements.
Nondestructive testing applications for determining when concrete pavements can be opened to traffic are also discussed. Additionally, case studies from Iowa, Georgia, Ohio, California, Virginia and Indiana are presented.
• Enhancing Performance with Internally Cured Concrete (EPIC2): Featured in the August EDC News Biweekly Newsletter, this article describes an evaluation of the use of internally cured concrete on three bridge deck projects in Idaho and Georgia to minimize shrinkage and other cracking. After more than two and a half years in service, the featured bridge decks with internally cured concrete are performing very well at minimal additional costs (0.7%).
• Field Monitoring of Wicking Geotextile for Moisture Reduction in Pavements: A wicking geotextile product available on the market has been proven effective in removing water under both saturated and unsaturated conditions in limited laboratory tests and field projects. While most previous studies have used the product in unpaved and asphalt paved roads, this project evaluated its effectiveness for concrete pavement applications.
• New Additives Could Turn Concrete into an Effective Carbon Sink: A team at MIT has discovered that introducing sodium bicarbonate (baking soda) into concrete could significantly reduce concrete's carbon footprint without altering its bulk mechanical properties. Laboratory tests have demonstrated that up to 15 percent of the total amount of carbon dioxide associated with cement production could be mineralized. This new discovery suggests an optimistic future for the development of carbon neutral construction materials. The MIT team is continuing to research the durability impacts of adding sodium bicarbonate to concrete mixes.
Click here to access links to each of the above reports.
National Ready Mixed Concrete Association