China’s autoclaved aerated concrete is the earliest developed and most productive type of new wall materials. After more than 50 years of development, a complete industrial system of material production, equipment manufacturing, supporting material supply, design and scientific research has been formed. This is a lightweight material. It is made of cement, lime (containing calcium material), fly ash/ground sand (containing silicon material), aluminum powder (producing gas material) and a small amount of water, after quantitative mixing and mixing, the producing gas expands into a blank body without strength, after cutting and autoclaved curing and hardening.
In the process of wall material innovation, autoclaved aerated concrete block has become the main force to replace small clay brick. Ninety-eight percent of the autoclaved aerated concrete in the country is block, used for masonry inside and outside walls. Its volume density ranges from 500 to 800 kg/m3, which is equivalent to 1/3 ~ 1/5 of ordinary sand concrete and 1/2.5 ~ 1/3.5 of clay solid brick. Of course, its compressive strength cannot be high, only 2.5 ~ 10 mpa, can be used as a non-load-bearing filled wall, can also be used for load-bearing wall by special structural treatment, and even with rustproof steel bars for load-bearing wall.
At present, the vast majority of autoclaved aerated concrete products in China are blocks. In foreign countries, the ratio of autoclaved aerated concrete blocks to panels is almost 6:4. In high-rise buildings, aerated concrete panels are commonly used, not only for internal and external walls, but also for floor and roof panels with reinforcement. According to the research and analysis, in the residential buildings of different family types, except the reinforced concrete frame system, the total amount of interior and exterior wallboard and floor board accounts for about 46% of the volume of structural components ~ 59% of prefabricated houses. In other words, if the internal and external wallboard and floor board are changed to autoclaved aerated concrete panel, the structural dead weight of the entire building will be reduced by about 1/4, the saving resources will be a huge number, but also because of the use of aerated concrete internal and external wallboard and floor plate to the reinforced concrete load-bearing structure of the economy.
It can be seen that the degree of standardization of autoclaved aerated concrete panels is very high, and its specifications and dimensions can be produced by aerated block factories at present. However, the weight of individual parts and spenders is within 1 ton, which is quite different from the current situation that the entire exterior wall panel and floor slab of common concrete are usually 5 tons, or even have to be installed by a crane of 10 tons. Autoclaved aerated concrete slates of different specifications are cut from large slabs, and there is no problem of manufacturing, depreciation and scrap of reinforced concrete component molds, which is also a contribution to energy conservation and emission reduction. Strictly speaking, only when the internal and external wall panels and floor slabs are converted to use standardized components, rather than concrete components “customized” for specific projects, can they be truly standardized, standardized and industrialized, which is the greatest advantage of autoclaved aerated concrete panels.