Recycling glass fiber-reinforced plastic in asphalt concrete production

Abstract

<abstract> <p>Glass fiber-reinforced plastics (GFRP) have been produced in large quantities for over half a century and nowadays their waste has become a problem worldwide. Their recycling is difficult because they are predominantly manufactured from thermosetting matrices that are not suitable for secondary processing. Only few technologies are able to target full-scale utilization of residual mechanical performance at recycling, with the replacement of gravel in asphalt concrete being one of them. The possibility of introducing crushed GFRP (GFRP crumb) into asphalt concrete and its impact on mechanical characteristics have been investigated in our study. As the source of GFRP, road noise-protection fence was chosen due to large quantities of its waste accumulated in urban economy. Several approaches to produce crumbs were attempted with only shredding being successful. The GFRP crumb has provided excellent mechanical performance of asphalt concrete fabricated by standard routine. In particular, the improvement in compressive modulus was 40%, even under conditions of elevated asphalt concrete temperature at 50 ℃. Besides, introduction of GFRP crumb reduced the overall weight of asphalt concrete mixture, providing further reduction of a carbon footprint. The results obtained indicated that recycling of GFRP waste as replacement of gravel in asphalt concrete provides an economically and environmentally safe solution.</p> </abstract>