Virtual mechanical testing of asphalt mixture based on X-ray computed tomography

In order to study the relationship between the microstructure and the mechanical performance of asphalt mixtures, a program was developed using on Matlab to make three-dimensional reconstruction of computed tomography image slices. The model was input into ANSYS to make meshing, and indirect tensile test simulation was conducted. The specimen deformation and strain distribution within the mastic and the aggregate were calculated. The research results revealed that the deformation and strain distributions on two sides of the specimen were not symmetrical, and the maximum stress within the mastic was not located in the center of the specimen. In addition, the strain within the mastic was much greater than that within the aggregate. The results suggest that the improvement of the asphalt binder property should be taken into account when designing an asphalt mixture so that early-age plastic deformation and late-age cracking due to greater localized binder strain can be avoided.