Utilization of fly ash cenosphere as lightweight filler in cement-based composites - A review

Fly ash cenospheres (FACs) are the hollow spherical particles obtained during coal burning process in coal fired power plants. FAC has been used as a lightweight filler (LWF) material in producing lightweight cementitious composites (LWC) since 1984 and currently many researchers are widening the knowledge in this area. In this paper, the research activities and outputs regarding the application of FAC in civil engineering are reviewed systematically. The influences of FAC on the mechanical, functional and structural properties as well as on the durability of FAC incorporated cement-based composites (FACC) are summarized. The higher specific strength of the composites modified by FAC can be attributed to the thicker and tougher FAC shell as well as the partial pozzolanic activity of FAC particles in cementitious systems. Future prospects for its use are also suggested in this paper.