Performance space diagram for the evaluation of high- and low-temperature asphalt mixture performance

This paper presents a simple, yet powerful method for simultaneously evaluating the high- and low-temperature performance of asphalt paving mixtures for the purpose of mixture design, evaluation, and forensic investigation. A performance-space diagram approach is described, with an emphasis on Hamburg-DC(T) plots presented in this paper. Specifically, a plot of Hamburg wheel tracking results, plotted in reverse order on the y-axis using an arithmetic scale, along with DC(T) fracture energy results, plotted on the x-axis, constitutes the Hamburg-DC(T) plot. Plotting candidate mixture designs, research results, and so on yields a surprising amount of insight into mixture variables that affect overall performance. For instance, substitution of one straight-run binder grade for another results in a clear, predictable trade-off in the Hamburg-DC(T) performance space. Polymer-modified grades, on the other hand, provide a more beneficial shift in the Hamburg-DC(T) space. The benefits of using this approach in the design of mixtures containing recycled asphalt mixture and recycled asphalt shingles is also presented. Effects of rejuvenators and the benefits of stone-mastic asphalt designs are also demonstrated. Finally, a broad look at a large database of mixtures recently designed in Illinois is presented.