Effect of basalt fibre on the performance of composite cement concrete mixes at elevated temperature

Knowledge of the performance of concrete at elevated temperatures is crucial for structures exposed to fire or extreme heat. In this study, the impacts of basalt fibre (BF) reinforcement on the mechanical and durability properties of concrete mixes under high-temperature exposure (200–800°C) were investigated. BF dosages of 0%, 0.3% and 0.5% by volume of binder were used, and the mixes were tested for fresh and hardened concrete properties, and their durability in extreme heat. The compressive and flexural strengths, water absorption, sorptivity and chloride ion penetration were evaluated. The results showed that the addition of BF improved workability, with mixes with 0.3% BF achieving a flow of 790 mm. Mix CCM 8, with 0.5% BF, exhibited the highest 28-day compressive strength of 63.90 MPa, compared with 52.76 MPa for the control mix. Durability tests reveal reduced water absorption (1.10%) and improved sorptivity, indicating better resistance to moisture and ion penetration. This study highlights the potential of BF to enhance concrete's mechanical and durability properties, offering a promising solution for fire-resistant high-performance construction.