Evaluation of Recycled Plastic (PET) Effects on Mechanical Properties and Abrasion Resistance of Concrete Pavements

The vulnerability of non-biodegradable wastes and their exploiting to reduce contamination of environment has been abundantly attracted the engineers’ attention. In addition, the abrasion resistance of concrete pavement is one of the prominent factors of durability causing non-affordable maintenance and rehabilitation costs. Thus, utilizing plastic wastes either as aggregate replacement or fiber is considered as an eco-friendly idea. Recently, numerous studies have been carried out to investigate the effects of PET (with different shapes and sizes) on mechanical properties and durability characteristics of concrete. In the present research, 5%, 10%, 15%, 20%, 25% and 30% by volume fraction of natural river sand in concrete mixes were replaced with recycled PET and specifications of fresh and hardened concrete so as to evaluate mechanical properties and abrasion resistance of concrete specimens. The obtained results revealed that replacing recycled PET aggregates with natural sand decreases slump and fresh density of concrete. Nevertheless, the mechanical properties were degraded as PET content increased. Furthermore, the results that replacing up to 30 percent of PET resulted in reducing compressive, splitting tensile and flexural strength, respectively, 36, 42 and 22 percent compared to control sample. In addition, replacing fine recycled PET improved the abrasion resistance of concrete. According to criteria implied by standards, the experimental results admitted that replacing 20% of fine recycled PET resulted in the most possible mechanical behavior and abrasion resistance.