Structural concrete using sintered flyash lightweight aggregate: A review

Abstract

The utilization of industrial waste as a construction material is a big leap towards sustainable development. Flyash is a waste material obtained from thermal power plants during combustion of pulverized coal. The research in relation to the use of sintered flyash aggregate to produce structural lightweight concrete is summarized in this paper. The manuscript discussed about the constituent parameters of the aggregate such as physical and chemical properties of flyash as well as binders, the pelletization parameters such as angle of inclination, rotation speed and duration of pelletization process and its influence on the aggregate properties. Also, the paper discussed about the sintering parameters such as temperature and duration of sintering and its significances. The physical and mechanical properties of the sintered flyash aggregates were also briefed. The review of literatures show that the specific gravity of these aggregate was 16–46% less than that of the normal weight aggregates and possess higher water absorption. The fresh, mechanical and durability properties of the concrete produced with sintered flyash concrete were also summarized. Sintered flyash aggregate concretes have the 28-day compressive strengths in the range of 27–74MPa, with densities in the range of 1651–2017kg/m3. The durability properties of the flyash aggregate concretes indicate that the performance is satisfactory for structural applications. The review indicates that sintered flyash aggregate concrete is one of the potential materials for the development of structural concrete.