Characterisation of asphalt mixes containing MSW ash using the dynamic modulus |E*| test

Municipal solid waste incinerator ash was used to replace fine aggregate in hot-mix asphalt concrete with up to 40% by aggregate weight in the mix. Mix design was performed according to the Marshall mix design method to find the optimum asphalt content for different mixes. The dynamic modulus |E*| test was conducted on all mixes. |E*| master curves were developed. The curves were compared with Witczak's predictive model. Shift factor equations were developed and compared with the proposed equation in the Mechanistic–Empirical Pavement Design Guide (M-E PDG). |E*|/sin δ was used as an indicator for the rutting potential of the mixes. The results indicated good agreement between the developed master curves and the predictive model for the control mix (conventional mix), while significant difference was noticed for the ash mixes. The M-E PDG shift factors were found to lie in the middle of the developed factors. The increase in ash content in the asphalt layer is expected to result in higher rutting.