Research on Mechanism of Architectural Wastes Solidified by Alkali-Activated Cement and Fly Ash

An comparison research on the effect of pozzolanic reactions of fly ashes in architectural wastes recycle is described in the paper. In the experiment, NaOH and Na2SO4-Ca(OH)2 were used to activate the pozzolanic activities in the fly ashes—cement system to solidify the architectural wastes. The macro and micro testing methods were used to test the compressive strength, phase and electronic micro morphology of the hydration of alkali-activated fly ashes—cement cementitious system. The testing result shows that proper alkali-activated fly ashes—cement cementitious architectural wastes can shorten the incubation time of the pozzolanic reactions of fly ashes, whi ch make the reactions of fly ashes more sufficient. So the hydration products of fly ashes —cement cementitious system with alkali additions were more than those of without alkali add itions, and the compressive strength of the alkali-activated fly ashes—cement cementitious system is higher than that of non alkali-activated fly ashes—cement cementitious system.