The Study on Reactivity and High-Strength Mechanism of Modified Fly-ash Concrete

This paper discusses reactivity and high-strength mechanism of modified fly ash concrete by DSC, SEM and DTA. The result indicates the shape effect, activation effect and micro-aggregate effect of the modified fly ash is developed sufficiently. The reactivity of modified fly ash concrete is enhanced obviously. The binder material of modified fly ash hydration heat is much more than the original fly ash´s. The hydration products of concrete which is made with modified fly ash contain much less CH and more C-S-H gel, and the each day strength of concrete is higher and interfacial transition zone of concrete improved obviously. Grains of modified fly ash are smaller, so it can be scattered into cement paste better to make the pores of concrete subdivided and filled.