The influence of short and long term aging on the dynamic modulus of recycled polyethylene asphalt mixture

Abstract

The asphalt pavement and plastics industry has been promoting recycling waste plastic to produce hot asphalt mixes because of the potential economic and environmental benefits. Although the influence of aging on features of asphalt mixture using traditional polymer additives has been relatively elucidated, the research on mixtures using recycling Polyethylene (rPE) additives has been an ongoing topic. This study investigated the influence of the long-term oven (LTOA) and short-term oven (STOA) on the dynamic modulus of asphalt mixtures. rPE was formulated by adding 0.6% to aggregates using the dry process. The control mixtures used different binders, including 60/70 penetration grade and styren- butadien-styren modified binder (PMB). After mixing, the loose mixtures were short-term aged for 4 hours at 135 °C, following long-term aged for 5 days at 95°C. The results showed that, the dynamic modulus |E*| of STOA asphalt concrete mixtures was lower than that of LTOA asphalt concrete mixtures. When compared with rPE and PMB mixtures, virgin mixtures changed more significantly in LTOA. Moreover, rPE and PMB modified mixtures have lower |E*|LTOA/|E*|STOA ratios compared with virgin mixtures. Dynamic modulus of rPE mixtures in both STOA and LTOA was almost equivalent to PMB mixtures.

Keywords

• short-term aging
• long- term aging
• dynamic modulus
• recycling polyethylene