RT Journal Article
T1 Radon diffusion coefficient of cement pastes made with recycled thermal carbon fly ashes
A1 Castaño Casco, Elena
A1 Caño Blanes, Andrés
A1 Suárez Navarro, José Antonio
A1 Gutiérrez-Alvarez, Isidoro
A1 Barba Lobo, Alejandro
A1 Bolívar Raya, Juan Pedro
A1 Alonso, M. M.
AB The use of supplementary cementitious materials (SCMs) is one of the most used ways to reduce CO2 emissions associated with the production of Portland cement. However, many of these SCMs are Naturally Occurring Radioactive Materials (NORM), which present naturally occurring radionuclides. Radon emission from these types of materials, together with radon infiltration from the ground through them, is one of the main sources of indoor radon. These pathways through the building materials are regulated by the radon diffusion coefficient, D. In this work, the radon properties of 7 cement pastes (at 2 and 28 days) were studied in function of the technical properties to determine their suitability as building and insulating materials against radon. Two main results were found: The D of the pastes changed by an order of magnitude between those with a 2-day curing time and those with a 28-day curing time, the latter being less permeable to radon, and there was also a decrease in D as the percentage of superplasticiser admixture increased, due to the reduction in the porosity of the final pastes and the reduction in radon permeability. The lowest D value obtained was of (4.3 ± 0.4) ·10-11 m2 s-1 for the paste with a 70% of cement, 30% of fly ash, 0.6% of superplasticiser admixture and 28 days of curing. In conclusion, it was found that different characteristics of the paste production, which influence the final microstructure, can produce cements containing NORM with permeabilities to radon low enough to be used as a radon barrier.
PB Elsevier
SN 0950-0618
SN 1879-0526 (electrónico)
YR 2025
FD 2025-01
LK https://hdl.handle.net/10272/25246
UL https://hdl.handle.net/10272/25246
LA eng
NO Castaño-Casco, E., Caño, A., Suárez-Navarro, J. A., Gutiérrez-Álvarez, I., Barba-Lobo, A., Bolívar, J. P., & Alonso, M. M. (2025). Radon diffusion coefficient of cement pastes made with recycled thermal carbon fly ashes. In Construction and Building Materials (Vol. 458, p. 139556). Elsevier BV. https://doi.org/10.1016/j.conbuildmat.2024.139556
NO This research was partially funded by different projects: the project funded by the Nuclear Safety Council (CSN) “Radon exhalation from building materials; Radiological impact and corrective measures (EXRADON)” (PR-047-2021), by grant PID2020-116461RB-C21 (RADREMOVE) funded by MICIU/AEI/10.13039/501100011033, by grant TED2021-130361B–I00 (RESTOREHU) funded by MICIU/AEI/ 10.13039/501100011033, as finally by research Project PID2020116002RB-100/AEI/10.13039/501100011033 (HORRADIONEX) supported the Spanish Ministry of Science and Innovation, the Spanish National Research Agency (AEI). The authors would also like to thank the MICIM for the pre-doctoral contract (PRE2021-098535) of Andr´ es Ca˜ no Blanes. We also thank Queralt Belen Marzal for her help in laboratory tests.Funding for open access charge: Universidad de Huelva / CBUA
DS Repositorio Institucional de la Universidad de Huelva
RD 31 may 2026