Study On The Effects Of Proceesing Parameters On The Performance Of Fly Ash Brick

China's per capita share of resourses is lower than the others. While, the production of clay solid brick not only destroyes soil ,but also costs a lot of energy, and pollutes the environment at the same time. As a result, the revelution of the wall materials is an inevitabal trend. Fly ash brick is an ideal alternative of clay solid brick because massive industry waste residue can be used and much energy can be saved in its production. But lack of systematic research makes the quality question a serious barrier in the promotion and application of fly ash brick.Beginning on the effects of curing rules on the development of strength of cement, cement-fly ash system and cement-fly ash-lime system, this thesis complyhensively studies the effects of the raw materials composion and fabrication technology on the compressive strength and frost resistance of fly ash brick. The aim of this thesis is to enrich the basic research on fly ash brick, and provide reference for the improvements of fabrication technology in the industy production.Experimental results indicate that compared with standard-cured, the compressive strength of cement samples will not improve unless after autoclaved and the compressive strength of the cement-fly ash samples and the cement-fly ash-lime samples improved a lot after both steam-cured and autoclaved. The increased rate of compressive strength of the cement-fly ash samples is 62%, highest after steam-cured, while the increased rate of compressive strength of the cement-fly ash-lime samples is 129%, highest after after autoclaved. The improvements of compressive strength and frost resistance of fly ash brick come along with the improvements of the cement content,the lime content, the sand content and the water content, but all the raw materials has a marginal value. The compressive strength and frost resistance of fly ash brick nearly not improve when the cement content and the sand content exceed their marginal value and the compressive strength and frost resistance of fly ash brick will reduce when the lime content and the water content exceed their marginal value. The compressive strength and frost resistance of fly ash brick will reduce when the fly ash content increases. The parameters in the fabrication technology also effect the compressive strength and frost resistance of fly ash brick. The improvements of compressive strength and frost resistance of fly ash brick come along with the increase of the settlement time, but the enhancement is little when the settle time exceeds 18h. The marginal value of constant tempreture time is 5h in steam-cured, lower or higher than the marginal value, the compressive strength and frost resistance of fly ash brick will not reach the best values. The compressive strength and frost resistance of fly ash brick will reduce when the tempreture increasing speed increases. In the study on frost resistance, the frost resistance reduces when the water-absorbtivity increases. The best content of the JDV air-entraining agents is 0.3‰and best content of the JC-2 air-entraining agents is 0.2‰. The optimum frost resistance will not be obtained without the best content of the air-entraining agents.