Effect of Fiber Reinforcement on the Mechanical and Flow Properties of Self-Compacting Concrete

Fiber Reinforced Self-Compacting Concrete (FRSCC) is an advanced form of Self-Compacting Concrete (SCC) that eliminates the need for vibration or mechanical compaction; it integrates the benefits of Fiber- Reinforced Concrete (FRC). The fibers within the mix help distribute loads more evenly, reducing stress concentrations and preventing crack propagation. This makes FRSCC particularly effective in applications where high performance and durability are crucial. High workability, segregation resistance, and concrete homogeneity are some of the essential properties of SCC. However, ensuring proper flowability while maintaining high strength poses a significant challenge. Therefore, a variety of admixtures, like supplementary cementitious materials, natural or synthetic fiber reinforcement, air entraining and viscosity-modifying agents, etc., can be incorporated to control and elevate the strength response of the concrete mix. This study primarily investigates the difference in strength and flow properties of FRSCC for multiple PCC variants with different dosage of nylon fiber to a maximum of 0.5% by volume. The flow properties of the concrete mix were assessed using V-Funnel, L-Box, T500, and slump tests. Subsequently, the hardened properties, such as compressive strength, split tensile strength, and flexural strength, were analyzed to evaluate the performance of FRSCC. The findings from this study indicate that using nylon fiber up to 0.25% by volume can increase the compressive strength capacity by 18%, the tensile strength by 45%, and the flexural strength by 29%. Additionally, failure in the FRSCC did not occur immediately in the three-point bending test compared to the SCC beam with no fiber. The FRSCC specimen could carry some additional load even after reaching its ultimate strength and developing flexural cracks.