The Fall 2024 newsletter of the National Concrete Consortium is now available online and includes the following items:
• Understanding Environmental Product Declarations (EPDs): The Fall 2024 NC² Moving Advancements into Practice (MAP) Brief from the NC² Resource Library examines the use of Environmental Product Declarations (EPDs) by federal, state and local government agencies aiming to reduce embodied carbon emissions. An EPD is an independently-verified report that communicates the embodied environmental impacts associated with construction materials.
• Toward the Development of Pavement-Specific Structural Synthetic Fibers: Dowel bars cannot be embedded in thinner concrete pavements or thinner concrete overlays due to insufficient concrete cover thickness. The critical distress in such cases is transverse joint faulting because of the lack of joint load transfer between the concrete slabs. It is therefore desirable to engineer a fiber that reduces joint faulting and increases joint performance. This study examined how the addition of synthetic fibers can aid in extending pavement design life through better joint performance..
• Bendable Concrete Utilized on a Bridge Deck (Engineered Cementitious Composite [ECC]): A major source of bridge deterioration requiring constant maintenance is mechanical expansion joints installed between adjacent simple span bridge decks. The University of Michigan has developed a ductile concrete (engineered cementitious composite [ECC]), commonly known as “bendable concrete,” to combat the many forms of concrete damage on bridge decks.
• Development of Cost-Effective Rapid-Setting Concrete for Improved Bridge Joint Performance: The Vermont Agency of Transportation has adopted the accelerated bridge construction (ABC) approach to deliver bridge construction and reconstruction projects. The focus of this research study was to conduct a comprehensive laboratory investigation of rapid-setting concrete (RSC) materials that are commonly used for field-placed ABC connections. Further, variations were evaluated to explore the potential for hybrid performance and proportion-based specifications.
• Solutions to Mitigate Dowel/Tie Bar Propagated Cracking – Phase 1: This Phase 1 study was undertaken to evaluate cracking related to dowel bars and tie bars in concrete pavement. The results of the literature review and field studies suggest that under some conditions, restraint caused by dowel bars and tie bars in the concrete results in high early-age stresses that contribute to cracking. Field evaluation of six sites conducted as part of this research suggests that this type of cracking is not an isolated phenomenon.
Click here to access the Fall 2024 newsletter and links to each report summarized above.
National Ready Mixed Concrete Association