The effect of recycled PET bottles on the fracture toughness of polymer concrete

Abstract

Abstract In this study, recycled polyethylene terephthalate (PET) bottles are shredded in different sizes and added to the polymer concrete composition to investigate the effect on fracture toughness and fracture energy as well as an idea to reduce environmental pollution. In order to measure the mode I fracture toughness, center cracked Brazilian disk (CBD) specimens are manufactured with 20\xa0wt% epoxy resin and 80\xa0wt% quartz aggregate in the size of 2.4–4.75\xa0mm. Recycled PET fillers in two different sizes, i.e., fine (less than 2.4\xa0mm) and coarse (2.4–4.75\xa0mm) with 4\xa0wt% are added to the polymer concrete. Experimental results show that the addition of the fine and coarse PET filler materials to the polymer concrete mixture can increase the fracture toughness relative to the control material. However, the coarse PET filler can improve much more significantly the fracture toughness and fracture energy compared to the polymer concrete containing the fine PET filler. This is due to resistance made by the coarse PET filler via two energy dissipation mechanisms: a) crack growth through the matrix/PET interface by rounding the coarse PET filler; b) PET bridging. In addition, a linear relationship between the fracture toughness and fracture energy of tested polymer concrete mixtures was observed.