On the mechanical properties of concrete containing waste PET particles

Polyethylene Therephthalate (PET) is a kind of polymer which is used in manufacturing polyester fibers, bottle resin and engineering polyester in most of the countries around the world. Extensive application of this polymer in food packing industries and long-term decomposition of this kind of waste materials in nature encouraged many researchers around the world to find new ways to recycle and reuse them. In this article, with a more comprehensive approach than previous studies, effects of 5%, 10% and 15% substitution of sand with PET processed particles have been investigated. For this purpose, cubic and cylindrical specimens with different water to cement ratios were manufactured and physical properties of fresh concrete were evaluated. Moreover, the specimens cured in a standard condition were used in an experimental program to obtain mechanical properties. Results indicate that fresh concretes containing PET particles presented lower workability and density. Concrete with PET particles demonstrated lower modulus of elasticity and splitting tensile strength with respect to conventional concrete. The compressive and flexural strength show an ascending trend at the initial stages, however, they tend to decrease after a while. On the other hand, ultrasonic pulse tests revealed a porous structure for concrete containing PET particles.