Hydration Performance and Pore Structure of Fly Ash-Cement Pastes

Abstract:

The hydration performance and pore structure of fly ash-cement (FC) pastes were investigated by means of XRD, TG, ex-situ leaching (ESL) and MIP. The results reveal that the influence of curing age to the kinds of hydration products of FC pastes is unconspicuous. As the content of fly ash increase, the Ca(OH)2 content decrease gradually. However, the content of Ca(OH)2 left in every paste is almost constant after 28d, regardless of the replacement ratio of fly ash and water-binder ratio. The decline of alkalinity of pore solution is not endless, even though the contents of fly ash in FC pastes is very high(65%).The incorporation of fly ash in proper ratios could increase the ratio of harmless pores and improve the microstructure of the FC pastes. Ca(OH)2 was not consumed heavily or exhausted when cementitious material was hydrated due to the low reaction degree of fly ash.

• Periodical: Applied Mechanics and Materials (Volumes 204-208)
• Pages: 3867-3871
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.204-208.3867
• Online since: October 2012
• Authors: Xiang Li*, Yun Dong, Hua Quan Yang
• Keywords: Calcium Hydroxide, Cement, Fly Ash (FA), Hydration, Pore Structure

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