RESEARCH ARTICLE
The Effects of Change in Fineness of Fly Ash on Air-Entraining Concrete
Hongzhu Quan*
Article Information
Identifiers and Pagination:
Year: 2011Volume: 5
First Page: 124
Last Page: 131
Publisher ID: TOCIEJ-5-124
DOI: 10.2174/1874149501105010124
Article History:
Received Date: 7/11/2010Revision Received Date: 20/1/2011
Acceptance Date: 10/2/2011
Electronic publication date: 29/4/2011
Collection year: 2011
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: https://creativecommons.org/licenses/by/4.0/legalcode. This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
Although the specific surface area of type-2 fly ash, specified to be not less than 250 m2/kg in Japanese Industrial Standard, type-2 fly ash manufactured and available range from 300 m2/kg to 450 cm2/kg in Japan. In order to make clear of the effects of change in fineness of fly ash on the properties of air-entraining concrete, 2 series of laboratory experiments were carried out using 6 kinds fly ash with the specific surface area in the range from 250 m2/kg to 440 m2/kg. In the series 1 experiment, mix proportion was the same for 6 mixtures of fly ash, regardless of the change in fly ash properties. Water binder ratio, unit binder content, fly ash replacement ratio and unit water content were constant for all mixtures as well as the dosage of chemical admixture. In the series 2 experiment, 5 mixtures of concrete with the same materials, with the same unit binder content, with the same fly ash replacement ratio and with the same water binder ratio as those in the series 1 experiment were examined. However, unit water content and dosage of air-entraining agent were adjusted to obtain target slump and target air content. The test results indicated higher slump and lower air content and higher dosage of air-entraining agent for fly ash with higher specific surface area than those with lower specific surface area. Compressive strength was found to increase with the increases of specific surface area of fly ash, while drying shrinkage and carbonation were found to show different tendency with change in fineness of fly ash.
