Research On Development Of Non-autoclaved Fly-ash Aerated Concrete

Wall materials are an important component of buiding envelope,in residential buildings the external walls of the heat consumption of the total heat loss accounts for about 35% to 45%.With the increasingly serious situation of energy, energy consumption of building energy saving rapid growth, making building energy efficiency become increasingly important.China's coal consumption has become the world's single largest country, fly ash emissions increased dramatically, and effective recycling of fly ash can realize a win-win of environmental and economic benefits.According to the present situation and domestic consumption of resources, So we must empolder and promote various kinds of new wall materials,which can saving the plantation,consuming little energy,using the waste,and be propitious to our environment. this is also make a good opportunity and vast development space for the development and application of insulating material provides.Therefore, Aerated concrete as a kind of lightweight wall material received attention for its unique combination of superior strength,lightweight,heat insulation and processability.This paper utilize the fly-ash from Chongqing electricity generating station for main raw material to produce Non-autoclaved Aerated Concrete.Firstly the paper studied the factors of raw material level influence on the performance of products, determining the production process in autoclaved aerated concrete which prepared at the initial mixing ratio. on this basis, then combining with the activity of fly ash excitation mechanism and the active mineral admixture on properties of concrete mechanisms, adding admixtures in combination with active mineral admixtures can significantly improved the performance of fly ash aerated concrete, the experimental results show that ground of triethanolamine, sodium and slag powder can significantly improve the performance of the products. Thermal curing process in the preparation of aerated concrete under the age 5days,its strength and density grade reached the standard request to a B08 level of autoclaved aerated concrete.Samples of SEM analysis showed that the preparation of aerated concrete hydration products have great difference between standard maintenance and thermal curing maintenance. In the standard curing condition of hydration products with lower crystallinity, the gel is much more; but under curing conditions of the thermal curing, the mainly form of hydration products was CSH (B) gel, and The structure formation of Aerated concrete is better.Aerated concrete thermal performance test results show that, compared with other kinds of common masonry structure, Non-autoclaved fly-ash aerated concrete owns the biggest of thermal resistance ,the minimum thermal conductivity and density. Therefore, using the Non- autoclaved fly-ash concrete wall as thermal insulation material in the building maintenance structure, has significant economic and social benefits.