CARBON DIOXIDE BINDING ABILITY IN CONCRETES: METHODOLOGY AND MODELING

Author(s): L. Schmitt, J. Jeong, J-M Potier, L. Izoret, J. Mai-Nhu, N. Decousser, P. Rougeau
Paper category: Proceedings
Book title: CO2STO2019 - International Workshop CO2 Storage in Concrete
Editor(s): Assia Djerbi, Othman Omikrine-Metalssi, Teddy Fen-Chong
ISBN:
e-ISBN: 978-2-35158-232-9
Publisher: RILEM Publications SARL
Publication year: 2019
Pages: 56
Total Pages: 1
Language : English

Abstract: Carbonation of concretes is a natural physico-chemical process that can be described as a
reaction between the carbon dioxide contained in the air and some calcium ions of the hydrates
of the cement matrix. Carbonation concerns not only all concretes in contact with the ambient
air but also concretes in ground, from production stage to use and end-of-life stages. The
amount of carbon dioxide bound varies according to the type of binder, the compacity of
concrete and the environmental conditions during use and end-of-life stages. To take into
account the re-carbonation of concrete, works have been carried out within the framework of
the European standardization group CEN TC104 / SC1 / TG20. A methodology to take into
account the re-carbonation of concrete structures has also been proposed in the NF EN 16757
standard on environmental product declarations for concrete and concrete elements. This is
an important topic towards a sustainable development in the current context of circular
economy and CO2 uptake related to energy labelling (E+C-).
In this article, several numerical and analytical carbonation models are used to estimate the
CO2 binding ability of typical concrete structures. The goal is to specify the parameters that
should be considered when dealing with the re-carbonation of concretes and to prioritize
influential parameters. The results of the different models are compared to the methodology
proposed in Appendix BB of NF EN 16757 standard. The first results confirm that the
methodology described in the NF EN 16757 standard leads to estimated degree of carbonation
of the same order of magnitude. The advantage of using more advanced models lies in a better
consideration of environmental parameters, the possibility to simulate the behaviour of crushed
concrete, its reuse in new concrete as recycled aggregate and the possibility to simulate the
carbonation of concretes in ground. This is an immediate perspective in the ongoing work in
the French national project FastCarb.

Online publication : 2019
Publication type : full_text
Public price (Euros) : 0.00