Influence of Mineral Mixture Performance on Dynamic Modulus of Hot Mix Asphalt

In order to solve the problem of high temperature performance of asphalt mixture, an investigation into the influence of mineral mixture performance on the dynamic modulus of hot mix asphalt (HMA) was conducted. Nine various AC-20C gradations were determined in accordance with a Bailey method parameters based on orthogonal experimental design. The performances of the mineral mixtures with each gradation were evaluated by using the California bearing ratio (CBR) and the voids of vibrated aggregate (VVA) in laboratory. Three gradations with significantly different mineral mixture performances were picked out to make HMA. Then, the dynamic moduli of HMAs corresponding to each of the 3 gradations were tested under multiple temperatures and loading frequencies. The influence of mineral mixture performance on the dynamic modulus of HMA was analyzed in accordance with the experimental results. The results show that the mineral mixture performance has significant influence on the dynamic modulus of HMA at high temperature, while has almost no influence at low temperature. The high temperature performance of HMA can be improved through investigating the CBR and VVA of aggregate in design. Higher CBR and lower VVA imply better high temperature performance of HMA.