Usage mineral additive at production of autoclaved aerated concrete

Energy is the unchangeable need of these days, and the importance of the energy economy shows itself every day. Wasting energy also creates environmental and economic problems. A significant part of our countrys wastage of energy is related to heating. Therefore, the productivity that will be provided in this area will bring significant benefits. One way to save energy on buildings is to use wall materials with low thermal conductivity. "Autoclaved aerated concrete (AAC)", a building material developed in Sweden in the late 1920s is a lightweight concrete that is produced under special conditions by adding mix, pore-forming aluminum, which consists of natural raw materials such as cement, silica sand, gypsum and lime. AAC is a durable construction material that provides fire safety with fire resistance (A1 class), building safety by lightness (by reducing earthquake loads) and thermal insolation by its porous structure. In this study, the use of fly ash, silica fume and blast furnace slag as raw material in the production of AAC has been investigated. In addition to the basic materials that compose AAC, varied mixtures were obtained by adding fly ash, silica fume, blast furnace slag in proportions of 3, 6, 9, 12 and 15% instead of a part of cement. A total of 16 varied mixtures were prepared. Experimental samples were cured in an autoclave at a pressure of 12 bar for an average of 8 hours. Some physical and mechanical properties of the test specimens have been investigated. Microstructure studies were also carried out on selected samples. The results obtained were evaluated comparatively.