The Research Of Heat-insulating Aerated Concrete Block

As resources increasingly scarce and a large amount of solid waste produced, how toreduce the energy consumption of building and improve the building energy efficiencystandards and recycles waste resources has become a hot topic. With the deepening of buildingenergy efficiency, ordinary autoclaved aerated concrete has been difficult to meet65%of theenergy efficiency standards, it is also has provided a broad space platform for the research ofheat-insulating aerated concrete block.The heat-insulating aerated concrete block is made by improving ordinary aeratedconcrete technology and it has low density, high strength and low thermal conductivityperformance. Moreover, the exterior wall masonry structure with it could reach the standard ofbuilding energy efficiency65%, without relying on any other thermal insulating materials.This paper aimed at the preparation of B03aerated concrete block, and the main rawmaterial is GGBS、cement and oil shale ash. Main raw materials was studied on the influenceof the autoclaved aerated concrete in the test. Combined with orthogonal test analysis results,the main raw materials mix proportion was determined primarily. On this basis, the experimentusing different excitation approach to optimize the performance. Combined with the SEMphotos, XRD pattern and the coefficient of thermal conductivity meter method, we studied andanalyzed the respective excitation mechanism, and the influence of excitation material on themicrostructure, the hydration products, strength and the heat conduction coefficient.Research findings are as follows:1.The activity of GGBS is higher and the28d activity index is as high as95%. Oil shaleash is a kind of siliceous material, it can provide plenty of SiO2for hydrothermal synthesisreaction, to generate the hydrated calcium silicate hydration products, that is beneficial to thestrength of the aerated concrete. Adequate dosage of slag powder and oil shale ash hassignificant effect to improve the performance of the body and the aerated concrete.2.We determined the optimum prescription and production technology by orthogonalexperiment: Oil shale ash35%, Mineral powder25%, cement25%, slurry temperature35℃, hydrogen peroxide4.0%, ratio of water to material0.60and stable foam agent A0.09%.3.Mechanical grinding can improve the grain size distribution of oil shale ash and its performance, that is helpful to the improve the performance of the aerated concrete. The resultsindicate that the suitable duration of grinding for shale ash is20min4.In the experiment, the influence of the chemical activation on property of aeratedconcrete is studied. Chemical excitation agent: triethanolamine, sodium sulfate and sodiumsilicate. Stimulating effect: sodium silicate> sodium sulfate> triethanolamine. Among them,sodium silicate can significantly improve the performance of aerated concrete. Sodium silicatehas a function of the stabilizing hydrogen peroxide, that Could effectively reduce the body gasrate and optimize the pore structure.5.The influence of the mineral admixture on property of aerated concrete is also studied inthis paper. Mineral admixture: natural gypsum, fluorine gypsum and phosphorusgypsum.Similar to the natural gypsum, fluorine gypsum and phosphorus plaster,Especially thephosphorus gypsum, have good effects on improving the performance of aerated concrete.6.The preparation of aerated concrete performance is best when using physical stimulationand mineral additive: The unit weight is282kg/m3, The compressive strength is1.52MPa,Thethermal conductivity is0.0779W/(m·K).7.We also analyzed the basic properties of the aerated concrete block that is abandonedand analyzed the feasibility of its use in the aerated concrete in this paper. Through the contrasttest analysis, the effect of waste block on the properties of waste block is determined. It haveprovided some reference data for reusing waste block. Tests have shown that adequate dosageof waste block could promote the synthesis of hydrothermal reaction which is conducive toimprove the performance of the product.