Effects of Environment-friendly Polymer Composite Modifiers on the Modulus and Pavement Performance of Asphalt Mixtures

Abstract

Background: In the current context of low-carbon environment, it is particularly important to use waste plastics to prepare modifiers that increase the modulus of the bituminous mixture. Objectives: The study aimed to find out the influence of environment-friendly polymer composite modifier (E-FPCM) on modulus and pavement performance of bituminous mixture. Method: The influence of the optimum component E-FPCM on the dynamic modulus (DM) has been explored. The E-FPCM content’s effect on the rheological properties of bitumen has been analyzed. Also, the influence of E-FPCM on pavement performance has been analyzed. Results: The degree of influence on SR of bituminous mixture has been in the order of recycled low-density polyethene (R-LDPE) > aromatic oil > lignin fiber. The optimum composition of E-FPCM has been found to be 10% aromatic oil, 4.8% C9, 62% R-LDPE, 7.0% lignin fiber, 0.2% antioxidant 1076, 2% silane coupling agent, and 14% mineral powder. By using E-FPCM with the optimum components, the SBS bituminous mixture or 90# bituminous mixture has been found to meet the standard of a high-modulus bituminous mixture (HMBM). E-FPCM has been found to reduce the phase angle (δ) of bitumen and increase the complex shear modulus (G∗) and rutting factor [G∗/sin(δ)], which may help improve the rutting resistance (RR). Conclusion: E-FPCM is beneficial for improving the RR of the bituminous mixture, and reasonable content of E-FPCM has a great role in improving the water stability (WS) and low-temperature crack resistance (LTCR) of the bituminous mixture.