AASHTO TP 131-18 (2020) PDF Download

AASHTO TP 131-18 (2020) is a standard that provides a method for determining the dynamic modulus of asphalt mixtures using the indirect tension test. The dynamic modulus is an important property that relates to the pavement's ability to withstand dynamic loading and resist fatigue cracking. This test method is applicable for both dense-graded and gap-graded mixtures, with a maximum aggregate size of up to 25 mm.

The test involves subjecting cylindrical asphalt specimens to a dynamic load while monitoring the resulting strain and stress. The specimens are initially loaded to a specified stress level, and then a sinusoidal load is applied at a given frequency and temperature. The resulting strain amplitude and phase angle are measured and used to calculate the dynamic modulus. The standard provides detailed procedures for specimen preparation, testing conditions, and calculations.

By determining the dynamic modulus of asphalt mixtures, this standard enables engineers and researchers to evaluate the performance characteristics of different asphalt mixtures under varying loading conditions. This information can then be used to design and optimize asphalt pavements to better withstand the demands of heavy traffic and harsh environmental conditions.