Problems with Variability in Using Fly Ash in Mixed Cement

Abstract:

The use of fly ash as a substitute for cement clinker brings some benefits, but also problems. One of the biggest problems of using fly ash in general is its high variability. This paper is dedicated not only to the variability of fly ash in the Czech Republic, but the issue of different water absorption of fly ash is described here as well. In addition, one of the options for coping with variability is stated here. If we follow one of the main indicators for sorting fly ash, which is the grading curve, we can optimize the use of ash produced. Based on grading curves, the mixing of various ash fractions was optimized with regard to the porosity of the mixture. Porosity has a direct effect on the compressive strength of the resulting material. This optimization will subsequently be verified experimentally.

• Periodical: Advanced Materials Research (Volume 969)
• Pages: 308-311
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.969.308
• Online since: June 2014
• Authors: Ondřej Zobal*, Pavel Padevět, Vít Šmilauer, Zdeněk Bittnar
• Keywords: Cement, Fly Ash (FA), Optimization, Variability

References

[1] P. Fečko, Fly Ash, VŠB - Technical University of Ostrava. 187 p., ISBN 80-248-0327-5, 2003, p.122 – 163.

[2] ČSI: ČSN 72 2071, Fly ash for building industry purposes. Common provisions, requirements and test methods, Prague, 2000, p.36.

[3] W. Berg, et al. Handbuch Flugashe im Beton. CEZ GROUP. 167 p., ISBN 978-80-260-4226-6, 2013, p.12 – 13.

[4] T. Reschke, Der Einfluss der Granulometrie der Feinstoffe auf die Gefugeentwicklung und die Festigkeit von Beton, Ph.D. Thesis, Weimar, (2000).

[5] J. Keil, et al. The Construction of Orlik - Proceedings of the State, The National Company of Water Building, 1966, 515 p.