Performance Engineered Mixtures for Concrete Pavements in the US

Many concrete pavement mixtures in the US are proportioned based on recipes that have been used before, or on prescriptive specifications. As budgets grow tighter and increasing attention is being paid to sustainability metrics, greater attention is beginning to be focused on making mixtures that are more efficient in their usage of materials, yet do not compromise engineering performance. While the technology is largely available in the concrete industry, a number of challenges are slowing the development of more performance-based specifications and mixtures in the US market. These include resistance to change from familiar to less known, resistance to any change in the distribution of risk, and a lack of good performance tests. This paper addresses these factors by clearly laying out the barriers to adoption of more performance-based specifications for mixtures, along with identifying the research that is needed to address them. Suggestions are made on the steps that can be taken to move the process forward. The paper also discusses work recently conducted to investigate an alternative approach to mix proportioning that is better able to deliver designed performance requirements for local materials.