Investigate the Behavior of Mechanical Properties of Concrete with Coconut Fiber

This study explores the mechanical behavior of coconut fiber-reinforced concrete (CFRC) as an environmentally friendly alternative in the construction industry. Coconut fiber, a natural and sustainable material, possesses high tensile strength and ductility, making it a promising additive to enhance the toughness and crack resistance of concrete. The primary objective of this research was to investigate how different proportions of coconut fiber-specifically 0%, 0.25%, 0.50%, 0.75%, and 1.00% by weight of cement-affect the compressive and tensile strengths of concrete. A total of 90 standard cylindrical specimens were prepared and tested following ASTM C39 and ASTM C496 protocols, with 45 cylinders used for compressive strength tests and 45 for split tensile strength tests after 28 days of curing. The experimental findings indicate a general decrease in compressive strength as coconut fiber content increases. At 1.00% fiber content, the compressive strength showed up to a 61.7% reduction compared to plain concrete. This decline is attributed to the irregular distribution of fibers and the increased voids within the concrete matrix. However, tensile strength exhibited a more nonlinear pattern. While low fiber content (0.25% and 0.50%) resulted in moderate strength reductions, some specimens at 0.50% fiber content approached the tensile performance of plain concrete. Higher fiber percentages (0.75% and 1.00%) caused more significant tensile losses, likely due to fiber clumping and disruption of matrix integrity. Despite reductions in strength, the inclusion of coconut fiber improved post-cracking behavior and energy absorption capacity, making CFRC a viable option in applications where ductility and resistance to dynamic or impact loads are prioritized over compressive strength. Moreover, the use of coconut fiber aligns with sustainable construction practices by utilizing agricultural waste and reducing the environmental impact of concrete production. This study concludes that while excessive coconut fiber content can negatively impact strength, optimized dosages can offer performance benefits in specific applications, supporting the potential of CFRC in eco-friendly and cost-effective construction solutions.