Virginia Transportation Research Council Report - Evaluation of BMD Surface Mixtures

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Balanced Mix Design (BMD) is an asphalt mixture design method that replaces some aspects of traditional volumetric design with performance testing for the most common distresses, such as rutting and cracking. This approach provides an opportunity to properly design and produce engineered asphalt mixtures, including those with higher reclaimed asphalt pavement (RAP) contents, recycling agents (RAs), fibers, polymer modified binders, and so on. The results of laboratory performance tests play a crucial role in the BMD process because they ensure the production of high-performing materials. In addition to performance testing and evaluation in the laboratory, accelerated pavement testing serves as a valuable tool to bridge the important and significant gap between models developed using laboratory material characterization and actual long-term pavement performance monitoring.

The purpose of this study is to evaluate the application of the BMD concept to design durable and longer lasting surface mixtures with A and D designations in Virginia, with a focus on relatively higher RAP contents, or HRAP mixtures, (that is, greater than 30% RAP). A and D mixtures are designated for traffic loads of 0 to 3 million and 3 to 10 million equivalent single axle loads, respectively. The scope of work consisted of laboratory and accelerated pavement testing of six surface mixtures incorporating a range of RAP contents (conventional and high), two binder grades, one RA, and one warm mix additive.

The full report is available by following this link.