Concrete Infrastructure: Recent Advancements and Needs with a Focus on North America

This letter provides an overview of the continent’s diversity in geography and climatic exposure and the impact of chlorides on reinforced concrete structures in North America. Several research needs are identified, including those that arise as specifications begin to change from prescriptive to performance-based approaches. Further, the widespread changes in material compositions or chloride exposures, require important changes to specifications, design practices, or maintenance procedures. Related to reducing carbon emissions, there is a need to reduce clinker content in concrete mixtures, increase the use of novel cementitious and supplementary cementitious materials (SCM), and to understand the durability of such concretes. The following research efforts from a North American context are warranted: (i) investigating the long-term durability of novel cement and SCM systems, including non-Portland cement-based materials and those made with CO₂ mineralization used to meet carbon emission targets; (ii) understanding climate change impacts of temperature and sea levels, including flood impact, on chloride exposure and chloride-induced corrosion; (iii) developing rapid and reliable tests to estimate durability in practice, particularly for scaling, freeze-thaw, salt damage, and chloride-induced corrosion; and (v) developing better understanding of the short and long-term implications of changes in constituent materials and exposure.