Effect of the Ca-to-Si ratio on the properties of autoclaved aerated concrete containing coal fly ash from circulating fluidized bed combustion boiler

摘要

The Ca-to-Si (C/S) ratio appropriate for autoclaved aerated concrete (MC) containing fly ash from pulverized coal combustion (FCC) boiler may not be equally suitable for AAC containing fly ash from circulating fluidized bed combustion (CFBC) boiler. We investigated the effect of the C/S ratio on the properties of MC containing CFBC fly ash, using MC containing FCC fly ash as the control. Results showed that MC containing CFBC fly ash and MC containing PCC fly ash have distinct properties. Furthermore, the C/S ratio affects the properties of MC containing coal fly ash by altering the hydrates and pore structure of the MC. To achieve satisfactory mechanical properties, a higher C/S ratio should be adopted for MC containing CFBC fly ash as compared with MC containing FCC fly ash. We confirmed that the C/S ratio of MC containing PCC fly ash should not be randomly applied to MC containing CFBC fly ash, owing to the unique properties of CFBC fly ash. Crown Copyright (C) 2015 Published by Elsevier Ltd. All rights reserved.