Alzaza, A., Ohenoja, K., Langås, I., Arntsen, B., Poikelispää, M., & Illikainen, M. (2022). Low-temperature (−10 °c) curing of Portland cement paste – Synergetic effects of chloride-free antifreeze admixture, C–S–H seeds, and room-temperature pre-curing. Cement and Concrete Composites, 125, 104319. https://doi.org/10.1016/j.cemconcomp.2021.104319
Low-temperature (−10 °C) curing of Portland cement paste : synergetic effects of chloride-free antifreeze admixture, C–S–H seeds, and room-temperature pre-curing
|Author:||Alzaza, Ahmad1; Ohenoja, Katja1; Langås, Isak2;|
1Fibre and Particle Engineering Research Unit, Faculty of Technology, University of Oulu, P.O. Box 4300, 90014, Oulu, Finland
2Department for Infrastructure, Materials, and Construction. Sintef Narvik AS, Postboks 250, 8504, Narvik, Norway
3Tampere University, Faculty of Engineering and Natural Sciences, P.O. Box 589, FI-33014, Tampere, Finland
|Online Access:||PDF Full Text (PDF, 17.5 MB)|
|Persistent link:|| http://urn.fi/urn:nbn:fi-fe2022042230134
|Publish Date:|| 2022-06-20
Cold weather drastically shortens the construction season in northern regions. Low ambient temperatures are known to have detrimental impacts on the reactivity and hardened performance of cementitious materials. This study therefore aims to assess the combined impacts of calcium silicate hydrate (C–S–H) seeds, binary chloride-free antifreeze admixture (i.e., urea and calcium nitrate), and short-period precuring at room temperature (23 ± 1 °C) on ordinary Portland cement (OPC) paste-cured at −10 °C. The heat of hydration, setting time, compressive strength, freezing point, frozen water amount, hydration products precipitation rate, water absorption, and permeable porosity were investigated experimentally. The best results in terms of compressive strength, degree of hydration, water absorption, and permeable porosity were obtained when C–S–H seeds, antifreeze admixture, and precuring were combined due to their mutual impacts. In the absence of room-temperature precuring, C–S–H seeds additive and antifreeze admixture showed negligible acceleration impacts on compressive strength development of subzero-cured paste. The incorporation of seeds and antifreeze admixture decreased the freezing points of the binders and thus protected the admixed binders against frost damage, and their effects were more obvious when combined with a few hours of precuring. The compressive strength of 28 d-old OPC paste modified by C–S–H seeds and antifreeze admixture and treated with precuring developed rapidly at −10 °C, gaining 96% (75.1 MPa) of that measured in control paste cured at room temperature (78 MPa), with comparable durability properties and a significant reduction of energy consumption and CO₂ emissions.
Cement & concrete composites
|Type of Publication:||
A1 Journal article – refereed
|Field of Science:||
218 Environmental engineering
216 Materials engineering
This work was carried out under the auspices of the ARCTIC-ecocrete project, which is supported by Interreg Nord program funded by European Regional Development Fund and the Regional Council of Lapland.
© 2021 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).