Abstract: The durability of concrete is a critical parameter governing the service life of structures, particularly under aggressive environmental exposure. The incorporation of recycled plastic fibres offers a sustainable approach to enhancing durability while addressing plastic waste management. This study experimentally investigates the influence of recycled plastic fibres on the sorptivity, water permeability, and chloride ion penetrability of M30 grade concrete. Fibres with varying volume fractions and aspect ratios were uniformly dispersed in the concrete matrix, and durability-related tests were conducted in accordance with relevant ASTM, DIN, and IS standards. The results indicate that fibre inclusion significantly modifies the pore structure of concrete, leading to reduced permeability and improved resistance to chloride ingress up to an optimum fibre content. Beyond the optimum dosage, fibre agglomeration adversely affects durability performance. The findings demonstrate that appropriately proportioned recycled plastic fibres can produce dense and durable concrete, contributing to sustainable construction practices without compromising performance.

Keywords: Concrete durability; recycled plastic fibres; sorptivity; water permeability; chloride ion penetration; sustainable concrete; fibre aspect ratio; permeability resistance; experimental evaluation.

Downloads: | DOI: 10.17148/IARJSET.2026.13124