Activation of fly ash cementitious systems in the presence of quicklime: Part I. Compressive strength and pozzolanic reaction rate

Antiohos, S; Tsimas, S

dc.contributor.author	Antiohos, S	en
dc.contributor.author	Tsimas, S	en
dc.date.accessioned	2014-03-01T01:19:52Z
dc.date.available	2014-03-01T01:19:52Z
dc.date.issued	2004	en
dc.identifier.issn	0008-8846	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/15735
dc.subject	Acceleration	en
dc.subject	Blended cement	en
dc.subject	Mechanical properties	en
dc.subject	Modeling	en
dc.subject	Quicklime	en
dc.subject.classification	Construction & Building Technology	en
dc.subject.classification	Materials Science, Multidisciplinary	en
dc.subject.other	Blending	en
dc.subject.other	Compressive strength	en
dc.subject.other	Curing	en
dc.subject.other	Fly ash	en
dc.subject.other	Hardening	en
dc.subject.other	Lime	en
dc.subject.other	Microstructure	en
dc.subject.other	Pozzolan	en
dc.subject.other	Rate constants	en
dc.subject.other	Reaction kinetics	en
dc.subject.other	Silica	en
dc.subject.other	Strength of materials	en
dc.subject.other	Alkali activation	en
dc.subject.other	Blended cements	en
dc.subject.other	Modeling	en
dc.subject.other	Reaction rates	en
dc.subject.other	Cements	en
dc.title	Activation of fly ash cementitious systems in the presence of quicklime: Part I. Compressive strength and pozzolanic reaction rate	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.cemconres.2003.08.008	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.cemconres.2003.08.008	en
heal.language	English	en
heal.publicationDate	2004	en
heal.abstract	In the first part of this study, the effect of industrially produced quicklime on the strength development and pozzolanic reaction rates of different fly ash/cement (FC) systems was investigated. Two high calcium fly ashes, diversified on their active silica and calcium oxide contents, and one with moderate calcium content were used. Strength development, hydration evolution, and pozzolanic reaction rates of the quicklime-fly ash-cement (QFC) systems were monitored and presented. Moreover, new efficiency factors were calculated for the activated systems in an attempt to optimize the quicklime addition in each case, whilst correlations were attempted between the nonevaporable water contents (W-n) and the cementitious efficiency factor (k values) of the activated systems. The addition of quicklime increased both the early and later strengths of the high-calcium fly ash specimens. For the two high-lime ashes tested, a 3% addition of quicklime was found to be the optimum dosage both for short and longer curing periods. It is possible that such an offer of lime fully employed the available silica from the ashes to form additional cementitious compounds, principally pozzolanic C-S-H. In the case of lower-lime fly ash, a small quantity of added lime (5%) was found to be effective only during the initial stages of the hardening process. When quicklime additions increased, no accelerating. effect was detected, as a result of the diminished proportion of soluble silica in the pore solution. Identification of the generated hydration products, porosity of the activated mixtures and examination of their microstructure will be presented in Part 11 of the study. (C) 2004 Elsevier Ltd. All rights reserved.	en
heal.publisher	PERGAMON-ELSEVIER SCIENCE LTD	en
heal.journalName	Cement and Concrete Research	en
dc.identifier.doi	10.1016/j.cemconres.2003.08.008	en
dc.identifier.isi	ISI:000224016900006	en
dc.identifier.volume	34	en
dc.identifier.issue	5	en
dc.identifier.spage	769	en
dc.identifier.epage	779	en