Non-autoclaved high strength cellular concrete from alkali activated slag

In this study, the use of alkali activated slag (AAS) in place of usual cementitious materials in the production of autoclave aerated concrete (AAC) was studied. This substitution altered autoclave curing stage by steam curing in AAC production process. In this way, after mixing of AAS paste with aluminum powder, enough time was given to the mixture. The resultant green body was then cured at 70, 78 and 87 °C. To achieve the best results, microscopic pore structure, compressive strength of the body and mini-slump of initial paste were studied. The results approved that AAC can be produced without autoclave by using AAS.

► Cellular concrete was made from sodium silicate activated blast furnace slag.
► High temperature curing was done at 85 °C for achieving a good strength compared to AAC.
► Pore structure was optimized by the proper amount of Al powder and sodium lauryl sulfate.
► Sodium silicate modulus was optimized for the best strength and pore structure.
► For reducing autoclave cost it can be replaced by AAC with this method.