Evaluation of Pre-Early Age Strength of Super Fine Ggbs Mortars


Evaluation of Pre-Early Age Strength of Super Fine Ggbs Mortars

K. Chaaruchandra, M. Cruickshank, R.P. West, J. Reddy

Abstract. This paper reports on a study exploring the use of a super-fine ground granulated blast-furnace slag (SF GGBS) for the precast industry wherein pre-early age strength becomes prominent for de-shuttering of formwork and optimizing productivity. The results will be discussed for research undertaken to study the effect of temperature curing methods, accelerating admixtures and SFGGBS on the compressive and flexural strength of standard mortars to establish the efficacy of the cement fineness and the new accelerator in very early age strength attainment. In this study a rapid hardening cement (RHC) is compared to a 50% SFGGBS to examine the effect of curing temperature (at 20 and 35 oC) and two new types of accelerating admixture on strengths at 6 different age of testing (16hr, 1, 2, 3 ,7 , 28 days). In comparison to pure RHC at 16 hrs, the SFGGBS mortars without admixture achieved only 35 % of flexural strength and about 30% of compressive strength at low temperature; whereas nearly 96 % of flexural strength and 100% of compressive strength at high temperature. With the addition of admixture 1, a new more effective admixture developed to activate SFGGBS, mortars achieved over 70 % of flexural strength and 60% of compressive strength at low temperature whereas over 128 % of flexural strength and 120% of compressive strength at high temperature. At 24 hrs the results are nearly similar to 100% RHC and with further increase in the age of the testing the results are found to broadly equate; thus demonstrating the effective performance of admixture 1 and higher temperature in activating SFGGBS for achieving better pre-early age strength.

Accelerating Admixture, Mortar, Pre-Early Age, Strength, Super-Fine GGBS

Published online , 9 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: K. Chaaruchandra, M. Cruickshank, R.P. West, J. Reddy, ‘Evaluation of Pre-Early Age Strength of Super Fine Ggbs Mortars’, Materials Research Proceedings, Vol. 7, pp 676-684, 2018

DOI: http://dx.doi.org/10.21741/9781945291838-65

The article was published as article 65 of the book Non-Conventional Materials and Technologies

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