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Rutting is a major distress for asphalt pavements. This paper examines the relationship of laboratory- and field-compaction methods to rutting performance based on aggregate packing charact...

This study presents the rutting performance results of full-scale pavement test sections subjected to F-15E and C-17 aircraft wheels at two different temperatures. Pavement structures for the tests were constructed under shelter in the U.S. Army Engineer Research and Development Center's (ERDC) pavement test facility. The full-scale test results are used to validate viscoelastic, viscoplastic and hardening-relaxation constitutive relationships implemented in the Pavement Analysis Using Nonlinear Damage Approach (PANDA) model. PANDA is a mechanistic-based model which incorporates nonlinear viscoelastic, viscoplastic, hardening-relaxation, viscodamage, moisture-induced damage and ageing constitutive relationships. Results of dynamic modulus and different repeated creep-recovery laboratory tests are analysed to extract the parameters associated with viscoelastic, viscoplastic and hardening-relaxation constitutive relationships implemented in PANDA. Once calibrated, PANDA is used to predict the rutting perfor...

In this study, the Asphalt Pavement Analyzer (APA) was investigated for its ability to detect asphalt paving mixtures designed for airfields that may be prone to rutting. The objective of t...

Cold-applied asphalt mixtures are often used for pavement repair, primarily because of the small quantities involved and/or the unavailability of hot-mixed asphalt. These cold-applied mixtures have poorer rutting resistance than hot mix asphalt because additives, often solvent, are required to provide adequate workability for them to be placed at ambient tempera-tures. This study primarily evaluated the rutting performance of nine commercial cold mix asphalt repair materials. Both laboratory wheel tracking data and field rutting performance were used in the evaluation with the focus on identifying suitable materials for repairing airfield pavements subjected to high-tire-pressure aircraft traffic. The commercial products included traditional cutback cold mixes as well as water-activated repair materials. Results from both laboratory and field rutting measurements showed that the water-activated materials outperform the products containing solvent. However, none of the commercial products achieved the target threshold of less than 1 in. rutting after 100 passes of simulated F-15E aircraft traffic. The laboratory wheel-tracking measurements proved to be a good indicator of field performance.

The results from accelerated pavement testing on warm-mix asphalt (WMA) mixtures designed for airfield pavements are presented. Three WMA mixtures and one hot-mix asphalt (HMA) mixture produced in an asphalt plant were evaluated under simulated heavy aircraft traffic. The evaluation was conducted at extreme traffic conditions, including heavy aircraft loading, high tire pressure, and high pavement temperature. Pavement structural response and rutting were evaluated to assess the susceptibility to permanent deformation of WMA mixtures compared with that of HMA produced with the same aggregate blend. Test results indicated that WMA was a viable product for surface mixtures on airfield pavements.

This paper presents the results of tests of warm-mix asphalt (WMA) mixtures designed for airfield pavements. The study was conducted in two phases. The first phase included laboratory tests on 11 WMA technologies. The tests in Phase 2 were performed on three WMA mixtures and one hot-mix asphalt (HMA) mixture produced in an asphalt plant. The evaluation included performance tests to assess WMA susceptibility to permanent deformation and moisture damage compared with that of HMA produced with the same aggregate blend. Test results indicated that WMA potentially was a viable product for surface mixtures on airfield pavements. Although WMA exhibited poorer performance than HMA in moisture damage tests on laboratory-produced specimens, the plant-produced mix indicated little difference compared with HMA. Rutting potential for WMA was somewhat greater than for HMA for mixtures produced both in the laboratory and in an asphalt plant according to asphalt pavement analyzer and Hamburg wheel tracking tests. Differences in performance of WMA mixtures were not attributed to a specific WMA technology category. Variations in performance test results between laboratory-produced specimens and plant-produced specimens were noted and indicated a need to require performance testing as part of a comprehensive quality assurance plan.

Hot-mix asphalt (HMA) laboratory mix design is intended to determine the proportion of aggregate and binder that, when mixed and compacted under a specified effort, will withstand anticipated loading conditions. Current mix design procedures that use the Superpave® gyratory compactor rely on the engineering properties and volumetrics of the compacted mixture to ensure reliable performance; however, a definitive performance test does not exist. The asphalt pavement analyzer (APA) was evaluated as a tool for assessing HMA mixtures designed to perform under high tire pressure aircraft following FAA specifications. The APA used in this study was specially designed to test simulated high tire pressures of 250 psi, which are becoming more common for aircraft. Thirty-three HMA mixtures were included in the study. Each was designed with the Superpave gyratory compactor, according to preliminary criteria being developed by FAA. The study included some mixtures that contain excessive percentages of natural sand and that do not meet FAA criteria. These mixtures were included to provide relative performance for mixtures expected to exhibit premature rutting. APA testing with the high tire pressure APA resulted in rapid failure of HMA specimens compared with traditional APA testing at lower pressures. Data were analyzed, with a focus on the provision of acceptance recommendations for mixtures to support high tire pressures. A preliminary 10-mm rut depth criterion after 4,000 load cycles is recommended.

A performance test, rather than an empirical test, to evaluate rutting susceptibility is needed to accompany current volumetric property requirements of airport hot mix asphalt (HMA) designed using a superpave gyratory compactor. The new performance test will provide a level of confidence that pavement constructed using a selected HMA mixture will function according to its design. This paper presents results from a laboratory study to identify a performance test for accepting hot asphalt mixtures for constructing airport pavements designed for high tire pressure traffic. Performance tests intended to indicate rutting susceptibility were performed on 34 HMA mixtures. Twenty-nine of these mixtures met all aggregate and volumetric property requirements for airport pavement construction; the remaining five mixtures were designed with excessive percentage of natural sand (30%) as rut-susceptible mixtures. Results from asphalt pavement analyzer (APA), triaxial static creep, and triaxial repeated load tests are presented. Statistical analyses performed on the results indicate that the rate of increase in permanent strain and the flow time value determined from triaxial static creep testing provide the strongest correlation to APA simulated traffic rutting.

The Asphalt Pavement Analyzer (APA) is a laboratory accelerated pavement test device that has been used by many researchers and agencies as a tool to assess rutting potential of asphalt mixtures. Typically, the test is performed on cylindrical or beam specimens using a vertical load of 445 N, a hose inflation pressure of 690 kPa, and a test temperature equal to the high binder performance grade (PG) temperature. A simulated wheel load is repetitively applied to test specimens, typically for 8,000 cycles, and the rut depth is measured as a function of load cycles. This study evaluated the sensitivity of the APA to specimen preparation procedures (e.g., mixing, compaction, and volumetrics) and test parameters (e.g., temperature, wheel load, and hose pressure). Results from the study indicate several parameters can have an important impact on APA performance. These influences become important considerations when using the APA as a design or performance assessment tool.

This report presents results from full-scale accelerated pavement testing of warm-mix asphalt (WMA) mixtures designed for airfield pavements. Three WMA mixtures were evaluated and compared to a control hot-mix asphalt (HMA) mixture. Data are presented from instrumented pavement test sections of WMA and HMA trafficked using a heavy-vehicle simulator (HVS-A) configured with an F-15E military jet aircraft wheel with a high load, high tire pressure and at high pavement temperatures. Surface permanent deformation is presented as a function of number of traffic cycles for the different pavement sections. Pavement instrumentation data are presented to show that rutting performance was not influenced by any differences in the structural capacity of the supporting layers. Additional testing was conducted on areas of the test sections not trafficked by the HVS-A to assess any potential problems associated with grooving the surface of WMA airfield pavements and to compare the performance of grooved WMA to that of grooved HMA. The results from this research demonstrated that WMA is a viable alternative to HMA for use on heavily trafficked airfield pavements.

Warm mix asphalt (WMA) technology is steadily gaining popularity due to the environmental, energy, and cost savings it offers as a sustainable alternative to conventional hot mix asphalt (HMA). However, adoption of WMA for commercial and military airfield pavements has been slow due to lack of documented good performance on airfields and concerns about potential rutting problems. This paper presents testing results for 11 WMA technologies, compared with traditional HMA. One unmodified base binder and one aggregate gradation were utilized throughout. Both laboratory full-scale plant-produced materials are tested. Binder performance grade (PG) data and Asphalt Pavement Analyzer (APA) mixture rutting data are presented. Relationships between laboratory and plant produced binder data and APA rutting are explored. The overall conclusion is that WMA is a viable alternative to HMA to improve the sustainability of airfield pavements.