Paving the way for a safer future
While our first Paper in our Education Series examined the role of SuperPave™- type testing, this second paper examines the wide range of significant benefits resulting from the implementation of SuperPave™- type performance-based testing and design.
It covers topics such as perpetual pavements, l-710 project in Long Beach (California), road user and societal benefits.
For some time, Governments and Highway Authorities have recognized the need to conduct performance-based testing during asphalt mixture design and pavement construction. Back in 2007, the US National Asphalt Pavement Association (NAPA) published the “National Asphalt Roadmap – A Commitment to the Future”.
The roadmap identified seven program areas, two of which directly relate to performance-based mix designs:
1. LONG-LIFE PAVEMENTS AND PAVEMENTPERFORMANCE VIA PERFORMANCE-BASED SPECIFICATIONS
Estimates indicate that a perpetual pavement may save as much as 20% asphalt binder and 25% aggregate over a 50-year design period. So, in order to ensure long-life pavements, specifications need to be developed that will indicate the quality characteristic of the materials that will deliver long-term performance.
2. MATERIALS CHARACTERIZATION AND MIX DESIGN
Evolutions in the selection of materials and advances in additives used in the design of special asphalt mixtures can significantly improve performance. But the use of new and innovative materials increases the need to understand how an asphalt mixture will contribute to performance and safety within a pavement structure.
The move towards performance-based testing
This has led to USA Congress, the Federal Highway Administration (FHWA) and State Highway Agencies (SHAs) requiring performance tests to be conducted for the selection of the optimum asphalt mixture for a specific pavement’s condition. Performance-based testing also supports programs such as the USA’s “Moving Ahead for Progress in the 21st Century” Act 2012 and “Fixing America’s Surface Transportation (FAST)” Act 2015 that requires US States to invest resources in projects that progress toward the National Performance goals, as set out in Table 1….