- Aggregate fracture in hot mix asphalt is affected by strength, gradation, and shape of the aggregate particles. This paper presents an approach for accounting for all these variables within asphalt mix and its effect on the mix performance. This approach combines the discrete element modeling and image processing techniques, it's developed through calibrating both aggregate and asphalt mixes experimental results. This approach showed promising results that can be used to investigate the internal force distribution with different mixes, and how different aggregates behave within one mix, and so this method can be used to select the more appropriate aggregate type for a given mix type. 2008 Taylor & Francis Group, London.