Main mechanical properties of recycled plastic strap fiber reinforced concrete based on destructive and non-destructive tests

The use of recycled strap plastic fibers, derived from industrial packaging waste, offers a sustainable approach to enhancing the mechanical properties of concrete while addressing environmental concerns. This study evaluated the effectiveness of recycled polyethylene terephthalate (PET) strap fibers, sourced from industrial packaging waste, in concrete mixes. Seven groups of specimens were prepared: one control group without fibers and six groups reinforced with fibers of aspect ratios 12.5 and 25. Each fiber-reinforced group was further divided into subgroups with volume fractions of 0.5%, 0.75%, and 1%. Mechanical properties were investigated using non-destructive tests, density measurements, and destructive tests for compressive strength, tensile strength, and modulus of elasticity. The results demonstrated that shorter fibers (aspect ratio 12.5) performed better than longer ones in enhancing mechanical properties, with 0.75% fiber volume fraction identified as optimal. Improvements of approximately 35%, 16%, and 26% were observed in compressive strength, splitting tensile strength, and flexural strength, respectively.