Mechanical, durability and microstructural properties of waste-based concrete reinforced with sugarcane fiber

Abstract

Extensive research has focused on producing sustainable concrete by exploring waste and recycled materials as alternatives to virgin substances. However, waste-based concretes often exhibit inferior durability and mechanical performance compared to traditional concrete. Incorporating reinforcement agents can enhance their performance. This study investigates the use of sugarcane fiber as a reinforcement in waste-based concretes containing fly ash (FA), ground granulated blast furnace slag (GGBS), and recycled concrete fine and coarse aggregates (RFA and RCA). Five dosages of sugarcane fibers (0 %, 1 %, 2 %, 3 %, and 4 % by fine aggregates mass) were examined. Mechanical and durability tests, including compressive strength, flexural strength, water absorption, and chloride ion penetration, were conducted. Scanning electron microscopy and micro-porosity analysis were employed for further assessment. Results show that adding sugarcane fiber enhances the waste-based concrete properties, with 3 % being the optimal dosage. This dosage improves compressive strength by 16 %, flexural strength by 35 %, flexural load bearing capacity by 34 %, energy absorption by 107 %, and toughness index by 6 %, while reducing water absorption by 4 % and chloride ion penetration by 23 %. Further increases in fiber dosage decrease concrete properties. The enhanced behavior is attributed to reduced porosity, refined pore structure, and reduced microcrack propagation. This study underscores the potential of incorporating sugarcane fiber along with waste materials to develop eco-friendly composites, aiming to mitigate carbon dioxide emissions and address environmental concerns.