Determining temperature and time dependent Poisson’s ratio of asphalt concrete using indirect tension test

• Studied temperature and time dependent Poisson’s ratio of asphalt concrete.
• Relaxation and cyclic load tests are done at different temperatures.
• Poisson’s ratio increases with time and temperature, however, not with frequency.
• Existing correlation between Poisson’s ratio and dynamic modulus is satisfied.

Poisson’s ratio (ν) of Asphalt Concrete (AC) is a fundamental input parameter to any numerical analysis based on elastic and viscoelastic constitutive properties. To this date, temperature- and time-dependent ν-value has been determined by either a static or a relaxation test at a single temperature in diametrical mode. This study, for the first time, performs relaxation tests at different temperatures in diametrical mode. In addition, cyclic load testing is conducted at different temperatures and loading frequencies to determine the temperature- and frequency-dependent ν-value of AC. Relaxation test results show that the ν-value of AC increases with testing time and temperature. Dynamic load test results show that ν-value of AC decreases with loading frequency; however, increases with temperature. To this end, measured ν-value of AC is compared with the ν-value predicted using model available in the new AASHTOWare Pavement Mechanistic-Empirical (ME) Design software. The measured ν-value matches with the predicted ν-value by the AASHTOWare Pavement ME Design software especially for AC that possesses high dynamic modulus.