Study On Preparation And Properties Of The Lightweight High-strengh And Energy-saving Block

At present, urbanization is in a rapid growth in our country. The flourishconstruction industry expanded the demand of wall material day by day. But theconsuming of land source to preparation traditional sintering wall material hasalready been widely noticed. Meanwhile, the natural environment was severelydamaged so that people’s living surroundings was ruined by the emission and stack ofindustrial solid waste of electricity, metallurgy, mining and so on. Against thisbackground, it has especially important significance of research of preparation oflight-weight, high-strength and energy-saving blocks and the influence of rawmaterial by making use of industrial solid waste. The research was funded byNational science and technology support project (2011BAJ03B03) and Hubeiprovince key point new product and process research and developmentproject(2012BAA10006). This article is mainly study on the influence of dosage andquality of raw materials and gas forming craft on light-weight (400-500kg/m3) fly ash(FA) autoclaved aerated concrete (AAC)’s slurry performance, products’ property andhydration products through preprocessing of two main raw materials, basing on(AAC) porous structure formation mechanism and strength formation mechanism ofautoclaved hydrothermal reaction. The main research and obtained importantachievement of this article as follows:1. Research of property of pretreated raw material.1) With ball-milling from0min to30min, the0.045mm square hole sieve screenresidue and specific surface area of FA change from17.8%to1.02%and313m2/kgto457m2/kg, respectively.2) The0.08mm square hole sieve screen residue of quick lime reduce from26.7%to2.7%after20mins’ ball-milling. Keep on prolonging ball-milling time willbe unhelpful on increasing the fineness.2. Influence of raw material dosage and fineness on AAC’s slurry, products propertyand hydration products.With the increasing of water to material ratio, the slurry extended degree gradually increased, the volume growth rate improved in the earlier stage, and it’sbeneficial on the reduction of dry density.With the quick lime dosage increasing from19%to29%, the slurry extendeddegree gradually decreased, the compressive strength increase of100%.With the increasing of quick lime fineness, the volume growth rate improve inthe earlier stage obviously, gas evolution increase of20.6%, compressive strengthincrease of38%, specific strength become maximizing,3884N m/kg, at LM2.The slurry extended degree become smaller with the increasing of FA fineness,meanwhile, the stability of the gas forming of slurry become better in the later stage.The specific strength first increases and then decreases.With the dosage of cement increases from6%to14%, it makes no difference ofslurry’s gas evolution and stability, the specific strength increase from4174N m/kgto4459N m/kg.3. Influence of composite foaming craft on AAC’s slurry and products property.1) The influence sequence of three different air entraining admixture onincrescent of slurry extended degree is AE-200＞PC-2＞K12, decreasing of drydensity is AE-200＞PC-2＞K12, reduction of compressive strength is K12＞AE-200＞PC-2.2) The higher dosage the entraining component add, the lower chemistryfoaming component shock on the slurry during the gas forming stage, the bettervolume stability the slurry will be.