Research On Preparation For Self-energy Conservation Of Fly Ash Aerated Concrete And The Thermal Property Of Masonry

With the development of economy and the remarkable improvement of people's living standard, energy consumption will be more and more. For that reason, building energy conservation is becoming the most important. Wall is the biggest area in the building of external structure, and its thermal insulation is intimate connection with building energy conservation. The development of new type wall material should be targeted at promoting the development of building energy conservation. The wall only consists of fly ash autoclaved aerated concrete block can obtain the desire of building energy conservation without other insulate material, it is self-energy conservation wall.In view of the problem of composite wall which has insulation layer, it is main discussed that the preparation for self-energy conservation of fly-ash autoclaved aerated concrete and research on the thermal property wall in the paper. By rational manufacturing and curing, low density of fly ash autoclaved aerated concrete, its dry density is 500 Kg/m3, is successfully produced, using of fly ash, cement and other raw materials. Based on the research of aerated time, pore content, aerated structure, the influence of slurry temperature, mixing time and aluminum powder on paste expansion is analyzed. The research indicated that the pore structure and compressive strength of autoclaved aerated concrete are well, when slurry temperature 40-50℃, aluminum powder 0.12%-0.14%, rapid mixing time 45s and slow mixing time 30s. On the basis of research on hardening time and compressive strength, raw materials and the method of curing having an effect on aerated concrete performance are discussed. The results show that autoclaved aerated concrete has good performance, when fineness of fly ash is 10%-15%, carbon content is a few, using of other raw materials are reasonable, and curing temperature is 45-50℃and humidity is 95%.On the basis of testing on fly ash autoclaved aerated concrete block which is low density, its performance is analyzed. The influence of different moistures on compressive strength and thermal conductivity is special studied. At the same time the micro-analysis of fly ash autoclaved aerated concrete is discussed. The thermal conductivity is 0.11W/(m·K), the acoustic absorptivity is 27.1%, the dryness of compressive strength is 4.31MPa. The thermal conductivity of fly ash autoclaved concrete masonry which has mortar joint and the axis compress of it are analyzed.In accordance with the requirement for standard for energy efficiency of building, it is calculated that economic thickness of self-energy conservation masonry consists of fly ash autoclaved aerated concrete. The temperature distribution and heat flux are simulated in the paper. At the same time, mortar joint thickness and mortar thermal conductivity which have an influence on self-energy conservation masonry are studied. The results demonstrated that when mortar joint thickness is 3mm and mortar thermal conductivity is 0.5 W/(m·K), the thermal property of self-energy conservation masonry is better. Designed different tectonic patterns of corner thermal bridges and T-wall thermal bridges, the temperature and heat flux of thermal bridges internal surface are simulated. And the condensation of thermal bridges is not appeared. The research show that self-energy conservation masonry consists of fly ash autoclaved aerated concrete is concentrated enclosure structure, energy efficiency, green building material on one, it has a broad market prospect.