Development of solid waste-based self-insulating material with high strength and low thermal conductivity

Abstract

Foam concrete as a thermal insulation material has been widely used to meet building energy conservation requirements. In this study, a low-clinker foamed concrete was prepared with an amount of solid waste, including fly ash, carbide slag, and glauber's salt, up to 80%. The effect of polycarboxylate superplasticizers (PCs) in the preparation process was examined to improve the mechanical properties of this particular system. The characteristic of hydration products and the pore structure was analyzed to illuminate the PCs influence on the hydration process. The outcomes demonstrate that the PCs can effectively improve the slurry's fluidity, enhance its compressive strength, and decrease its average diameter. Low-clinker foamed concrete's compressive strength reached 5.3 MPa, and its thermal conductivity reached 0.1556 W/(m·K). It was concluded that foam concrete has the potential to be widely used in green buildings due to its high strength and low thermal conductivity.