Use of Gypsum and CKD to enhance early age strength of High Volume Fly Ash (HVFA) pastes

Dali Bondar, Eoin Coakley

Research output: Contribution to journalArticlepeer-review

27 Citations (Scopus)


Use of higher proportions of fly ash as a cement replacement in concrete has obvious environmental and performance benefits but high volumes of fly ash are not commonly used due to perceived lower early age strengths. In this investigation, addition of cement kiln dust (CKD) and gypsum to activate the fly ash was studied and the proportions used in the paste mixes were designed to optimize the mixture ingredients to achieve the highest early age compressive strength. Change of mineral phase composition and micro structure of the composites was analyzed. It was found that CKD was much more effective in activating the fly ash than gypsum. Appreciable early age compressive strengths were achieved for fly ash contents up to 60% of the binder and these observations were supported by analysis of the mineral phases.
Original languageEnglish
Pages (from-to)93-108
Number of pages16
JournalConstruction and Building Materials
Early online date15 Sept 2014
Publication statusPublished (in print/issue) - 30 Nov 2014


  • High Volume Fly ash (HVFA) Concrete
  • Early age strength (EAS)
  • Cement klin dust (CKD)
  • Gypsum
  • Mineral phase


Dive into the research topics of 'Use of Gypsum and CKD to enhance early age strength of High Volume Fly Ash (HVFA) pastes'. Together they form a unique fingerprint.

Cite this