Sustainable approach to control autogenous shrinkage in low water–cement ratio concretes

Abstract This study investigated the effect of pre-saturated coconut fibres (CF) on the performance of high-performance concrete (HPC) under standard, membrane, and drying curing conditions. Mechanical and permeability related properties and autogenous shrinkage of HPC mixes were examined. Results indicated that CF proves beneficial for concrete cured in dry conditions, proving their internal curing effect. The tensile strength improved by 21–25 % in CF-reinforced mixes under drying conditions, demonstrating effective crack resistance. Water absorption increased minimally in fibrous mixes under moisture-deficient conditions, while chloride ion penetration was reduced, indicating improvement in durability. Autogenous shrinkage decreased by 18.5–65.2 %, depending on fibre dosage. These findings highlight the potential of pre-saturated CF to improve the performance and durability of HPC, particularly in environments with limited external curing.