Enhancing Concrete Properties through Fly Ash Pelletized Aggregates and Fibre Reinforcement - A Review

Abstract

This literature review examines recent studies in Lightweight Aggregate Concrete (LWAC), specifically focusing on utilizing fly ash pelletization and fibre reinforcement to enhance concrete properties. Fly ash, a by-product of coal combustion, has gathered attention because of its potential to be put forward as a critical component in creating lightweight aggregates. The process of pelletization, which involves forming fly ash into small, spherical pellets, has been shown to improve the mechanical properties of the resulting concrete. The process mainly includes the cold-bonded pelletization method, which consumes energy and is easy to use. The review gives fusion findings from various studies examining fly ash's role in producing lightweight aggregates and the impact of different additives and processes on the resulting material properties. Key insights reveal that incorporating silica fume, fly ash, and steel fibres remarkably improves concrete's compressive and bonding strengths. Additionally, the cold-bonded pelletization of fly ash and cement, especially when combined with Polypropylene (PP) and steel fibres, leads to enhanced aggregate properties, including strength, density, and water absorption. The review also highlights the importance of optimizing pelletization parameters and binder usage to improve the quality of lightweight aggregates and enhance the properties of concrete. Moreover, integrating hybrid fibres, such as carbon and polypropylene, enhances concrete's postpeak performance and flexibility. The findings suggest that these innovations in fly ash pelletization and fibre reinforcement improve mechanical performance and contribute to more sustainable and cost-effective concrete production. This review provides a comprehensive overview of the current state of research, offering insights into the future direction of LWAC development.