Experimental Investigation on Application of Coconut Fibre and Glass Fibre in Reinforced Concrete

This research presents an experimental investigation on the mechanical and durability properties of fibre-reinforced concrete using coconut fibre (CF) and glass fibre (GF) in M15, M20, and M25 grade concrete. The study aims to evaluate the effectiveness of natural and synthetic fibres in enhancing the performance of conventional concrete. Coconut fibre, being eco-friendly and sustainable, and glass fibre, known for its high tensile strength and durability, are incorporated in varying proportions of 5%, 10%, and 15% by weight (or volume, as applicable). A series of tests were conducted, including compressive strength, split tensile strength, flexural strength, and water absorption, at curing periods of 7, 14, and 28 days. Standard cube, cylinder, and beam specimens were prepared and tested as per relevant IS codes. The experimental results were compared with control concrete to assess the improvement in strength and durability characteristics. The findings indicate that the addition of fibres significantly influences the mechanical behavior of concrete. An optimum fibre content was observed at intermediate percentages (typically around 5–10%), beyond which workability decreased and strength gains were not proportionally significant. Coconut fibre improved crack resistance and ductility, while glass fibre enhanced tensile and flexural strength. However, excessive fibre content (15%) led to reduced workability and possible fibre clustering. Overall, the study demonstrates that both coconut fibre and glass fibre can be effectively used as reinforcing materials in concrete, contributing to improved performance and sustainability. The results provide valuable insights for the development of cost-effective, durable, and eco-friendly construction materials.