Evaluation of Simple Performance Tests on HMA Mixtures (9-558-S)

The Federal Highway Administration (FHWA) and the National Cooperative Highway Research Program (NCHRP) have sponsored or are sponsoring research projects that will lead to the development and validation of advanced materials characterization models and associated laboratory testing procedures for hot mix asphalt (HMA) (ie., NCHRP Projects 1-37A, 1-40, 9 -19, 9-29, and -930). Additionally, the two organizations are sponsoring development of a product currently called the 2002 Pavement Design Guide, which will lead, in part, to improved methods for designing flexible pavements and characterizing HMA material properties. The recommended test methods for the design guide focus on the complex modulus of compacted HMA material properties. The recommended test methods for the design guide focus on the complex modulus (E*) or dynamic modulus of compacted HMA materials but also involve accumulated axial strain from a repetative loading test (flow number) and tertiary axial strain from a static test (flow time). This series of test has been termed simple performance tests.