ABSTRACT
Different laboratory tests have been available to predict and compare the mechanical and engineering properties of asphalt mixes under different loading and environmental conditions. However, to predict and/or evaluate long-term performance of asphalt mixes indirect tensile fatigue and cyclic compressive laboratory tests have been utilized for many years. Most recently, the Asphalt Pavement Analyzer (APA) has been receiving much attention in the United States and Canada as a proof test for early detection of asphalt mixes susceptible to premature rutting and fatigue failure. In addition, the shear strength of asphalt mixes has been recognized by the Strategic Highway Research program (SHRP) as one of the strong candidates to describe and possibly predict long-term performance of newly constructed asphalt pavements. However, the correlation among these different test methods as well as the correlation between them and the pavement’s long-term performance still needs to be assessed. This investigation addresses these two points, where asphalt cores corresponding to five different mix types were tested in four different laboratory procedures. The parameters determined for each mix were the indirect tensile strength, resilient modulus, shear strength, shear modulus, and rut depth in the APA. The results of the indirect tensile strength and resilient were in excellent agreement, and the results of the shear strength, shear modulus, and rut depth were very close. However, the two groups had considerable differences, indicating that a single test may not be enough to predict the full extent of the asphalt long-term performance.
