Plant Fibres as Reinforcing Material in Self-Compacting Concrete: A Systematic Literature Review

Natural plant fibres have gained growing research interest as a construction material due to efforts to reduce the negative environmental impacts caused by construction activities. Many researchers have investigated the suitability of utilising plant fibres as reinforcement in self-compacting concrete (SCC) as a substitute for synthetic fibres, recognising that the production of synthetic fibres generates significant amounts of CO₂. In this study a bibliometric analysis was conducted to investigate the current research achievements and map the scientific studies where plant fibres were used in SCC. A detailed discussion on the effects of various plant fibres and their underlying mechanisms on the properties of SCC is also provided. The findings indicated that using plant fibres typically reduces the flowability, filling ability, and passing ability of SCC due to the high water absorption of plant fibres, fibre and aggregate interlocking, and the fibre agglomeration effect. Incorporating plant fibres increases the viscosity and enhances the segregation resistance of SCC due to the strong cohesion between plant fibres and the cement matrix. The inclusion of plant fibres usually improves the mechanical properties of SCC because of the synergetic effects of plant fibres on crack-bridging and strain redistribution across the cross-section of SCC. Adding plant fibres to SCC also reduces drying shrinkage and cracking due to the fibre bridging effect, while generally lowering the resistance to sulphate attack, acid attack, and freeze–thaw cycles and increasing the water absorption rate of SCC due to the increased porosity of the mix. A comprehensive overview of research gaps and future perspectives for further investigations is also provided in this study.