Flexural Behavior of Geopolymer RC Concrete Beams Containing Pet Waste as Sand Replacement

Abstract This study examines the flexural conduct of geopolymer concrete (GPC) beams, including polyethylene terephthalate (PET), used instead of sand with a water cementitious ratio of 0.125. Six size ratios of PET wastes were used 0%, 5%, 10%, 15%, 20%, and 30%. Six reinforced GPC beams (one sample per PET percentage) were tested to study the effects of PET on the GPC beams’ structural behavior. All beams are simply supported with measurements (0.15*0.2*1.4) m. Appropriate experiments were carried out to assess the strength properties of GPC mixtures with PET and were compared to the mix without PET wastes as a reference where compressive fracture energy is used to evaluate the GPC mixtures’ strength. The investigations of reinforced geopolymer concrete beams were detection ultimate load, ductility, energy absorption, cracking pattern, and stiffness. The outcome of the examination of reinforced geopolymer concrete beams with PET replacement (5%_30%) demonstrated an approximately 6.62%_7.76% increase in the ultimate failure load and a 6.63%_29.33% increase in initial stiffness. All beams demonstrated an increase in ductility of 20.22%_92.59%, with a 11.34%_44.07% reduction in secant stiffness, respectively, comparing with the reference beam.