Layer Placement of Recycled Tyre Steel Fibre Reinforcement on Rigid Pavement: Mechanical Performance and Engineering Implications

Abstract

This study evaluates the potential of reinforcing rigid pavement with steel fibres recovered from end-of-life tyres, addressing both structural performance and environmental sustainability. Traditional reinforcement methods, while effective, often lead to increased costs and sustainability concerns. The innovative use of recycled tyre steel fibres (RTSF) in rigid pavement concrete, leveraging their high tensile strength and crack-bridging capabilities, was explored by employing a strategic ‘layer placement’ approach with an adoption of the Building Research Establishment (BRE) mix proportioned for a 35 N/mm² characteristic strength at 28 days. Experimental results demonstrate notable improvements in compressive strength up to ≈ 18.05% with three layers of RTSF, while flexural strength gains were modest (≈ 0.49%), indicating potential for optimization. Additionally, the incorporation of RTSF reduced deflection, enhancing structural rigidity and overall stiffness of the pavement. This research not only addresses critical gaps in the mechanical behavior of RTSF-reinforced concrete but also underscores its environmental and economic benefits, supporting sustainable pavement design aligned with circular economy principles.