Evaluation of nondestructiveness of resonant column testing for characterization of asphalt concrete properties

The resonant column (RC) test has been used as a nondestructive test (NDT) to study dynamic properties of soils for the past few decades. With some modifications, this test can also be employed to characterize properties of asphalt concrete, especially because these properties are strongly dependent on the loading frequency. A conventional RC apparatus was retrofitted to characterize asphalt concrete properties at a range of temperatures from 10°C to 45°C. The RC test is believed to be nondestructive for most soils; however, this must be verified in case of testing asphalt concrete, especially at elevated temperatures. For this purpose, the impact resonance (IR) test, as a purely NDT tool, was used to check the integrity of asphalt concrete specimens before and after RC testing. The modulus values measured before and after RC tests, at each of the testing temperatures, were compared to evaluate the nondestructiveness of RC testing. Strain levels were also monitored to ensure that the material remained within the linear elastic range through the tests. The results show that the specimens exhibited the same modulus before and after RC testing over the full range of temperature and frequency sweep tests.