Bikram Baidhya

Concrete is one of the most extensively utilized construction materials today. Its popularity stems from its ready availability, ease of moulding into various shapes, cost-effectiveness, and high compressive strength. Despite these advantages, concrete is known for its low tensile strength and poor performance in harsh conditions, which is a significant drawback for any construction material. To mitigate these weaknesses, concrete is typically combined with steel reinforcement. Steel fibers are added to concrete to improve the structural properties, particularly tensile and flexural strength. Plain, straight and round fibers were found to develop very weak bond and hence low flexural strength. In this research, steel binding wires were used as steel fibers which are locally available at very cheap cost. Steel fibers were added in different percentage i.e. 0%, 0.5 %, 1%, 1.5%, 2%, 2.5% and 3%. The primary focus of the research was to calculate compressive and tensile strengths of various samples and determine the maximum amount of Steel fibers that can provide the maximum strength. To achieve this, cubes and cylinders were cast and tested using a Universal Testing Machine for their compressive and tensile strengths. The findings indicated a slight increase in compressive strength, while the addition of steel fibers resulted in a more significant increase in tensile strength.

Natural fibers are gaining attention for their benefits in both artificial and natural contexts. Using natural fibers in reinforced composites can reduce dependency on conventional concrete-making materials and mitigate environmental impact. This paper examines the effect of coconut fibers on the compressive strength of recycled aggregate (RA) concrete, focusing on the development of sustainable and ductile cementitious composites through the optimization of coconut fibers and construction waste. Specifically, the study investigates the impact of different percentages of coconut fiber (0%, 3%, 5%, and 7% by volume of the mix) on the compressive strength of concrete incorporating varying amounts of RA (0%, 25%, 50%, 75%, and 100%). The performance of these mixes was evaluated based on workability, density, and compressive strength (CS). The results showed that as the amount of RA increased, compressive strength decreased. To regain maximum strength, a preferable amount of 5% coconut fibers is required for each constant level of the water-cement ratio. Concrete incorporating 25% coarse RA with 5% coconut fibers exhibited compressive strength comparable to conventional concrete. The highest compressive strength for concrete made using 50% coarse RA with 0.3 water-cement ratio was achieved with 5% coconut fibers. This study recommends using 5% coconut fibers to attain optimal mechanical performance. The main scope of this paper highlights the potential use of coconut fibers in fibrous composites to partially replace conventional materials.