Effect of Recycled Polyethylene Terephthalate (PET) fibres on fresh and hardened properties of concrete: a review

Concrete is poorly tensile in strength and susceptible to cracking. Therefore, researchers have explored the incorporation of PET fibres into concrete as reinforcement. PET is a polymer commonly used in food and beverage packaging, and textile industry. This study reviews the fresh and hardened properties of recycled PET fibre-reinforced concrete (rPET-FRC). The workability, compressive, tensile, and flexural strength are investigated under factors such as rPET fibre volume, dimensions, water–cement ratio, and the use of blended cement. This review includes experimental results of previously conducted rPET-FRC research along with results gained from rPET-FRC where the rPET fibres are obtained from the same recycling plant. Furthermore, the experimental results are broadly elaborated by explaining the reasons behind the obtained results. This review is a valuable reference that offers insights into the effectiveness of rPET fibres in enhancing concrete’s overall mechanical properties. By highlighting the most effective rPET fibre volume fractions, water-cement ratios, and the influence of blended cement, this review enables researchers to optimise the design and application of rPET-FRC, promoting sustainable and innovative solutions in the global infrastructure sector. Further studies to be carried out in the future are recommended and existing research gaps related to rPET-FRC are also highlighted.