Joint effects of expansive admixture and fly ash on the carbonation rate of concrete

Title: Joint effects of expansive admixture and fly ash on the carbonation rate of concrete
Author(s): Zhonghe Shui, Liuqing Tu, Wei Chen, Juntao Ma, Wenbing Xu
Paper category : conference
Book title: 2nd International Symposium on Service Life Design for Infrastructures
Editor(s): K. van Breugel, Guang Ye, Yong Yuan
Print-ISBN: 978-2-35158-096-7
e-ISBN: 978-2-35158-097-4
Publisher: RILEM Publications SARL
Publication year: 2010
Pages: 205 - 212
Total Pages: 8
Nb references: 11
Language: English

Abstract: The use of expansive admixtures (EA) in concrete has become a common practice in China in various construction projects jointly with fly ash. While some researches focused on the joint effects of expansive admixtures and fly ash on the volume change and permeability of concrete, their effects on the carbonation rates are seldom investigated before. This study is aimed to evaluate the joint effects of the expansive admixture and fly ash on the carbonation resistance of concrete via the accelerated carbonation tests. Concrete mixes with different proportions of fly ash and expansive admixtures are prepared. The compressive strength and the accelerated carbonation rate of the concrete specimens are measured and microstructure of hardened concrete is analyzed with the coupled TG-DSC technique and Mercury Intrusion Porosimetry. It is shown that the carbonation rate is enhanced if EA is used jointly with fly ash in the concrete. The use of EA on one hand increases the amount of Ca(OH)2 in the concrete, and on the other hand coarsens the pore structure.

Online publication: 2011-04-20
Publication type : full_text
Public price (Euros): 0.00