Study On The Influence Of Admixture To Alkalifree Activated Of High Fly Ash Content Concrete

The high fly ash content concrete not only can reduce the hydration heat significantly, but also can reduce the risk of early cracking of concrete. Meanwhile,it is a very important factor that whether the ratio of water/cement of the high volume fly ash concrete can be reduced effectively and whether the activity of the fly ash can be fully played and the problem of strength in the earliest which restrict the development of that the high volume fly ash concrete.The law of high dosage admixture is explored by studying the influence of HmineralH HadmixtureH Hto the main properties of alkali-free activation of fly ash concrete and comparing the impact of different admixture of high fly ash content concrete performance improvement through the experimental data.This paper mainly studied from the following aspects:1. The physical and chemical properties of fly ashIn this article, research has been done systematically on the ingredients and the physical properties, chemical composition, mineral composition, particle characteristics of the fly ash by X-ray fluorescence spectroscopy, etc. It can determine that the amount of high-speed iron, high-alumina, lower-sulfur and high alkaline in the fly ash by comparison and analysis.The impact on the performance of different admixture of high fly ash content concreteResearch on properties of the work-ability, slump, strength and wear-resisting of the curing samples by proportional test using orthogonal design to explore the affect of properties of fly ash concrete.3. Explore the change mechanism of admixture for high fly ash content concreteBy SEM testing, analyzing the microstructure of high fly ash content concrete, to explore the extent of admixture influence and mechanism of concrete at high volume fly ash.With the affect of mineral admixture, the properties of fly ash concrete have improved to some extent. Not only the strength of the high volume fly ash concrete has improved, but also the other properties of the high volume fly ash concrete has improved,it creates conditions to the fully use of high volume fly ash concrete.