Carbonation resistance of high-volume fly ash (HVFA) mortar: effect of applied CO2 concentration

Author(s): Philip Van den Heede, Didier Snoeck, Tim Van Mullem, Nele De Belie
Paper category: Proceedings
Book title: SynerCrete’18: Interdisciplinary Approaches for Cement-based Materials and Structural Concrete: Synergizing Expertise and Bridging Scales of Space and Time Vol. 1 & 2
Editor(s): Miguel Azenha, Dirk Schlicke, Farid Benboudjema, Agnieszka Jędrzejewska
ISBN: 978-2-35158-202-2
e-ISBN: 978-2-35158-203-9
Publisher: RILEM Publications SARL
Publication year: 2018
Pages: 117-122
Total Pages: 6
Language : English

Abstract: To save time, the carbonation resistance of cementitious materials is usually assessed in an accelerated manner by exposing the material to CO2 levels that highly exceed the atmospheric CO2 concentration. However, a too high acceleration of the carbonation reaction could induce chemical, microstructural and mineralogical changes and excess production of the water reactant that are unrealistic. In this paper, it was evaluated whether the outcome of colorimetric carbonation experiments at 10% CO2 for High-Volume Fly Ash (HVFA) mortar could still be used for calculating natural carbonation rates and to do an adequate service life assessment. This seems not true. The effect of full carbonation at 10% CO2 on the capillary water uptake was also assessed gravimetrically and visually on neutron radiographs. This water uptake was found to be significantly lower than after full carbonation at only 1% CO2.

Online publication : 2018
Publication type : full_text
Public price (Euros) : 0.00