Challenges in using the Disc-Shaped Compact Tension (DCT) test to determine role of asphalt mix design variables in cracking resistance at low temperatures

AbstractThere have been many fracture tests – the Thermal Stress Restrained Specimen Test, the Single-Edge Notched Beam test, the Semi-Circular bend test, the Indirect Tensile Test and the Disc-Shaped Compact Tension (DCT) test – developed to understand thermal cracking in asphalt pavement. Among these tests, the DCT test is the most recent test method developed that has gained significant interest. This paper includes a laboratory study to measure the effect of different mixture design parameters on the DCT test results. The parameters include per cent binder replacement from recycled asphalt pavement, binder modification, low-temperature binder grade, oxidative ageing and mix design traffic level. To investigate the significance on the factors controlled, ANOVA and multi-linear regression analyses are used to show that only a few factors can be considered significant in terms of their effects on DCT parameters, and the significance of those factors could not explain the range in DCT response variables. ...