Report of RILEM TC 281-CCC: outcomes of a round robin on the resistance to accelerated carbonation of Portland, Portland-fly ash and blast-furnace blended cements

Hanne Vanoutrive; Philip Van den Heede; Natalia Alderete; Carmen Andrade; Tushar Bansal; Aires Camões; Özlem Cizer; Nele De Belie; Vilma Ducman; Miren Etxeberria; Lander Frederickx; Cyrill Grengg; Ivan Ignjatović; Tung-Chai Ling; Zhiyuan Liu; Inés Garcia-Lodeiro; Barbara Lothenbach; César Medina Martinez; Javier Sanchez-Montero; Kolawole Olonade; Angel Palomo; Quoc Tri Phung; Nuria Rebolledo; Marlene Sakoparnig; Kosmas Sideris; Charlotte Thiel; Talakokula Visalakshi; Anya Vollpracht; Stefanie von Greve-Dierfeld; Jinxin Wei; Bei Wu; Maciej Zając; Zengfeng Zhao; Elke Gruyaert

doi:10.1617/s11527-022-01927-7

Report of RILEM TC 281-CCC: outcomes of a round robin on the resistance to accelerated carbonation of Portland, Portland-fly ash and blast-furnace blended cements

Mater Struct. 2022;55(3):99. doi: 10.1617/s11527-022-01927-7. Epub 2022 Apr 4.

Authors

Hanne Vanoutrive^#¹, Philip Van den Heede^#², Natalia Alderete², Carmen Andrade³, Tushar Bansal⁴, Aires Camões⁵, Özlem Cizer⁶, Nele De Belie², Vilma Ducman⁷, Miren Etxeberria⁸, Lander Frederickx⁹, Cyrill Grengg¹⁰, Ivan Ignjatović¹¹, Tung-Chai Ling¹², Zhiyuan Liu², Inés Garcia-Lodeiro¹³, Barbara Lothenbach¹⁴, César Medina Martinez¹⁵, Javier Sanchez-Montero¹³, Kolawole Olonade¹⁶, Angel Palomo¹³, Quoc Tri Phung⁹, Nuria Rebolledo¹³, Marlene Sakoparnig¹⁷, Kosmas Sideris¹⁸, Charlotte Thiel¹⁹, Talakokula Visalakshi²⁰, Anya Vollpracht²¹, Stefanie von Greve-Dierfeld²², Jinxin Wei¹², Bei Wu²³, Maciej Zając²⁴, Zengfeng Zhao²⁵, Elke Gruyaert¹

Affiliations

¹ Department of Civil Engineering, Constructions and Materials, KU Leuven, Ghent Technology Campus, Ghent, Belgium.
² Magnel-Vandepitte Laboratory, Department of Structural Engineering and Building Materials, Ghent University, Ghent, Belgium.
³ Technical University of Madrid, Madrid, Spain.
⁴ Department of Civil Engineering, Bennett University, Noida, India.
⁵ Department of Civil Engineering, CTAC, University of Minho, Guimarães, Portugal.
⁶ Department of Civil Engineering, Constructions and Materials, KU Leuven, Leuven, Belgium.
⁷ ZAG - Slovenian National Building and Civil Engineering Institute, Ljubljana, Slovenia.
⁸ Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya·BarcelonaTECH, Barcelona, Spain.
⁹ Belgian Nuclear Research Centre (SCK-CEN), Mol, Belgium.
¹⁰ Institute of Applied Geosciences, Graz University of Technology, Graz, Austria.
¹¹ Department of Materials and Structures, Faculty of Civil Engineering, University of Belgrade, Belgrade, Serbia.
¹² College of Civil Engineering, Hunan University, Changsha, China.
¹³ Instituto de Ciencias de La Construcción Eduardo Torroja (IETcc-CSIC), Madrid, Spain.
¹⁴ Swiss Federal Laboratories for Materials Science and Technology (Empa), Laboratory for Concrete and Construction Chemistry, Dübendorf, Switzerland.
¹⁵ Department of Construction, Institute for Sustainable Regional Development (INTERRA), University of Extremadura, Cáceres, Spain.
¹⁶ Civil and Environmental Engineering, University of Lagos, Lagos, Nigeria.
¹⁷ Institute of Technology and Testing of Construction Materials, Graz University of Technology, Graz, Austria.
¹⁸ Department of Civil Engineering, Democritus University of Thrace, Xanthi, Greece.
¹⁹ Construction Materials, Regensburg University of Applied Sciences, Regensburg, Germany.
²⁰ Department of Civil Engineering, Mahindra University, Hyderabad, India.
²¹ Institute of Building Materials Research, RWTH Aachen University, Aachen, Germany.
²² TFB Technology and Research for Concrete Structures, Wildegg, Switzerland.
²³ Microlab, Faculty of Civil Engineering and Geosciences, Delft University of Technology, Delft, The Netherlands.
²⁴ HeidelbergCement AG, Global R&D, Leimen, Germany.
²⁵ Department of Structural Engineering, College of Civil Engineering, Tongji University, Shanghai, China.

^# Contributed equally.

Abstract

Many (inter)national standards exist to evaluate the resistance of mortar and concrete to carbonation. When a carbonation coefficient is used for performance comparison of mixtures or service life prediction, the applied boundary conditions during curing, preconditioning and carbonation play a crucial role, specifically when using latent hydraulic or pozzolanic supplementary cementitious materials (SCMs). An extensive interlaboratory test (ILT) with twenty two participating laboratories was set up in the framework of RILEM TC 281-CCC 'Carbonation of Concrete with SCMs'. The carbonation depths and coefficients determined by following several (inter)national standards for three cement types (CEM I, CEM II/B-V, CEM III/B) both on mortar and concrete scale were statistically compared. The outcomes of this study showed that the carbonation rate based on the carbonation depths after 91 days exposure, compared to 56 days or less exposure duration, best approximates the slope of the linear regression and those 91 days carbonation depths can therefore be considered as a good estimate of the potential resistance to carbonation. All standards evaluated in this study ranked the three cement types in the same order of carbonation resistance. Unfortunately, large variations within and between laboratories complicate to draw clear conclusions regarding the effect of sample pre-conditioning and carbonation exposure conditions on the carbonation performance of the specimens tested. Nevertheless, it was identified that fresh and hardened state properties alone cannot be used to infer carbonation resistance of the mortars or concretes tested. It was also found that sealed curing results in larger carbonation depths compared to water curing. However, when water curing was reduced from 28 to 3 or 7 days, higher carbonation depths compared to sealed curing were observed. This increase is more pronounced for CEM I compared to CEM III mixes. The variation between laboratories is larger than the potential effect of raising the CO₂ concentration from 1 to 4%. Finally, concrete, for which the aggregate-to-cement factor was increased by 1.79 in comparison with mortar, had a carbonation coefficient 1.18 times the one of mortar.

Supplementary information: The online version contains supplementary material available at 10.1617/s11527-022-01927-7.

Keywords: CO2 concentration; Carbonation; Cement; Curing; Fly ash; Ground granulated blast-furnace slag.