BMD round robin phase I testing complete

Like a summer vacation, the BMD Round Robin Phase I testing took a while to arrive, and once it did, it was over. With more than 46 sample sets distributed in Virginia and around the country, Ideal-CT index results were provided to the Virginia Transportation Research Council’s Dr. Stacey Diefenderfer for analysis. Except for the expected hiccups with a new procedure, the testing went very smoothly, according to VAA Director Mike Dudley. “A wide range of Ideal-CT manufacturers are represented in this Round Robin including the Humboldt HM-5125, IDEAL Plus, Auto_SCB, Pine Press with Smart-Jig and others. With all the specimens being produced in the same lab, this will be a great comparison of equipment.”

Now, Diefenderfer and her team at VTRC will pour over the data. Each lab received a mix with a high and low Ideal-CT index value. Both mixes were produced by VAA-member Bluegrass Testing Labs in Louisville, KY. The primary purpose for Phase I was to assess variability in results from two very different mixes based on equipment type assuming the lab technicians follow the same ASTM procedure. “We’ve tried to minimize as much variability in the material and specimens as possible so that we can address the concerns about the impact of equipment type with a robust data set. We appreciate all of the participating labs’ work; this has been a collaborative undertaking, and we believe that the results will benefit everyone. We’re already thinking about the next Phase—we know specimen preparation has a huge impact on test results and are planning to add that step to the next Round Robin effort,” said Stacey Diefenderfer.

The final results will be shared with participants and the broader asphalt community. Plan to attend the Mid-Atlantic Asphalt Expo & Conference in December to see a formal presentation. Also, consider participating in Phase II when a launch date is announced.

If you have any questions, contact Mike Dudley at