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The objective of this study was to assess the impact of aging on high polymer (HP)-modified asphalt binders when compared with conventional polymer-modified asphalt (PMA) binders on the basis of rheology- and chemistry-based parameters. An extended asphalt binder aging experiment that considered multiple combinations of PMA and HP binders from different sources was conducted. Long-term oven-aged asphalt binders at multiple temperatures and durations and asphalt binders aged in a pressure aging vessel (PAV) for multiple durations were tested using the dynamic shear rheometer. Several parameters were determined including low shear viscosity and Glover-Rowe parameters at various temperatures. The PAV-aged asphalt binders were further evaluated in terms of critical low temperature difference using the bending beam rheometer. All PMA and HP combinations were evaluated using Fourier transform infrared spectroscopy for characterization of chemical composition and assessment of polymer degradation. Overall, the measures indicated reduced susceptibility to aging of HP binders when compared with PMA binders, shown by a flatter slope with respect to oxidation with the low shear viscosity measures and Glover-Rowe parameters. In addition, the potential of polymer degradation for HP binders when compared with PMA binders was minimal with aging, thus indicating an increased longevity from a chemical-characteristic standpoint. [ABSTRACT FROM AUTHOR]

• Surrogate tests (e.g., APA, IDT HT, and IDEAL RT) matched rankings, aligning with APT evaluations. • AASHTOWare Pavement ME predicts rutting similarly for single/multiple RLPD test temps. Abbreviated calibration saves time and materials. • VDOT BMD spec recommends 8.0 mm APA rut depth for all categories. AASHTOWare predicts no failure (< 6.6 mm) & suggests 8 mm for D & 9.5 mm for A. • IDT HT and AASHTOWare Pavement ME suggest 105 kPa for A mixtures and 120 kPa for D mixtures. • IDEAL RT analysis: A mixture category – threshold RTindex 50. D mixture category – recommended RTindex 60. The balanced mix design (BMD) framework uses laboratory test methods to establish specifications that would ultimately be used for the design and acceptance of asphalt mixtures. Assembling such specifications is vital to optimizing the performance of asphalt mixtures for the distress of concern without violating any other criteria, consequently establishing the much desired "balance." This research presents a stepwise method towards the establishment of performance test threshold criteria for rutting evaluation only as part of a greater effort that the Virginia Department of Transportation (VDOT) is pursuing for the implementation of the BMD framework. Data and discussion of five performance tests addressing rutting performance, along with six representative Virginia mixtures, are presented. AASHTOWare Pavement ME analyses at the material level and project level were utilized to fine-tune observations obtained using the surrogate test methods for rutting evaluation. Potential routes and accompanying challenges towards establishing/refining performance criteria that would prove helpful to the ultimate adoption of BMD specifications were outlined. An example of proposed performance criteria based on the presented data is provided. The proposed performance thresholds for rutting evaluation are intended as indicative; for full development and implementation, further refinement of the values is warranted. [ABSTRACT FROM AUTHOR]

• Practical tests are essential for the implementation of Balanced Mix Design concept. • Monotonic tests are simple and quick performance indicator tests. • Monotonic tests can be used to assess the rutting potential of asphalt mixtures. • Implementation prospects for monotonic rutting tests are provided and discussed. Balanced mix design (BMD) is gaining popularity among highway agencies in the United States. That is because such concept allows innovations to be responsibly incorporated into asphalt mixtures, and quantifies the quality, where the volumetric properties and gradations alone cannot differentiate asphalt mixture performance. Additionally, such concept is expected to increase the durability and performance of asphalt mixtures. The BMD concept constitutes a series of different design alternatives and requires a suite of laboratory-based performance tests to be conducted on an asphalt mixture during the mixture design and production stages, thus making performance tests a critical part of the concept. Several monotonic loading test methods have emerged and been standardized to evaluate the cracking potential of asphalt mixtures in a straightforward manner. Similar monotonic loading tests have also been considered for evaluating the rutting potential of asphalt mixtures. This review provides researchers, transportation agencies, and practitioners with the state-of-art information on the use of monotonic loading tests to assess the rutting potential of asphalt mixtures, with particular emphasis given on the indirect tensile test (IDT) at high temperatures. The test methods documented in this work show the versatility of such tests in screening the rutting potential of asphalt mixtures. A set of considerations are also provided and discussed for implementation prospects of a monotonic loading rutting test. [ABSTRACT FROM AUTHOR]