A study of the properties of foamed lightweight aggregate for self-consolidating concrete

• Foamed lightweight aggregate (FLWA) with addition foaming agent was produced.
• Effects of foaming agent and surface treatment on properties of FLWA were assessed.
• FLWA was used as coarse aggregate for production of SCC.
• Workability and strength of SCC with FLWA were investigated.

This study investigated foamed lightweight aggregate (FLWA) manufactured with hydrogen peroxide (HP) as a foaming agent and using cold-bonded agglomeration process, a relatively low-polluting, energy efficient method of FLWA production. A number of the types of produced FLWA were surface treated to improve the performance of the aggregates. Moreover, 8 types of FLWA were used as coarse aggregate to produce self-consolidating concrete (SCC). A variety of tests were conducted to evaluate the effects of the foaming agent and the surface treatments on the properties of the cold-bonded lightweight aggregate. The workability, unit weight, and strength of the SCC specimens were determined in accordance with established standards. The FLWA type with the lowest specific gravity was binary mixture of 80% fly ash (FA) and 20% ground blast furnace slag (GBFS) at an HP concentration of 7%, which a specific gravity 1.27. The flowability, viscosity, and passing ability of all SCC mixtures met EFNARC requirements. Finally, the findings support that using foaming agent and modifying the surface of FLWA significantly affects the strength of SCC.