AASHTO T 321-17 (2021) PDF Download

The AASHTO T 321-17 (2021) standard is titled "Standard Method of Test for Determining the Fatigue Life of Compacted Asphalt Mixtures Subjected to Repeated Flexural Bending". This standard outlines the procedures for evaluating the fatigue life and fatigue energy of asphalt mixture beam specimens. These specimens are 389 mm long, 50 mm thick, and 63 mm wide, and they are either obtained from laboratory-compacted or field-compacted asphalt mixtures.

The test involves subjecting the asphalt mixture beam specimens to repeated flexural bending until failure occurs. The purpose of this test is to evaluate the performance and durability of asphalt mixtures under repeated loading conditions typically experienced in the field. The fatigue life and fatigue energy parameters quantitatively assess the resistance of the asphalt mixtures to fatigue cracking and provide valuable information for pavement design and material selection.