Influence of Asphalt Binder Properties on the Fatigue Performance of Asphalt Concrete Pavements

摘要

A number of studies have suggested that limits for the loss stiffness of the binder, G*sinδ, in the AASHTO binder specification is, by itself, not a sufficient indicator of the fatigue performance of asphalt concrete (AC) in asphalt pavement structures. To assist the Pacific Coast Conference on Asphalt Specifications (PCCAS) in deliberations pertaining to the AASHTO binder specification, this study was undertaken. The purpose of the study was to evaluate the influence of nine binders, selected by the PCCAS participants, on pavement fatigue performance for a representative range in pavement sections, environmental conditions, and traffic loading. The program has included: 1) tests on the binders to define their rheologic response over a range in temperatures and times of loading; 2) fatigue tests on mixes containing the binders; and 3) analysis of the simulated fatigue performance of the mixes in pavement structures in four environments of the Pacific region. With the exception of the thin AC pavement structure, mixes containing the nine binders provided adequate simulated fatigue performance (estimated ESALs equal to or exceeding design ESALs) at a 90 percent reliability level. Two alternatives for the binder fatigue requirement are briefly discussed, i.e., retain the current specification requirement or eliminate it. If the current fatigue requirement is eliminated, the question to be asked by the pavement community is what might happen without it? For example, could materials which are