Modelling of asphalt concrete - Numerical and experimental aspects

Some results of an extensive experimental and numerical research project on the response of Asphalt Concrete (AC) are presented. In the project, a material model for AC is being developed and implemented in the Finite Elements package CAPA-3D. Also, the test set-ups, instrumentation, and test procedures necessary to characterize the material and determine the model parameters were developed. In an early stage of the project, it was recognized that failure in tension and compression followed a different mechanism and needed to be described separately in order to capture the response to alternating loads. From the results of uniaxial tension tests it became apparent that also in tension pronounced non-linearity occurred prior to the peak load. The adaptations necessary to incorporate this in the model are presented in this paper. The response predicted by the model relations is compared to that observed in laboratory tests to validate the model relations and it can be seen that the observed behavior is described quite well by the model.