Behaviour of cementitious matrices subjected to the combined action of chloride ions and carbonation
| Autor: | Raphaele Lira Meireles Castro Malheiro, Gibson Rocha Meira, João Castro-Gomes, Maria Teresa Pessoa de Amorim, Rui Miguel Ferreira, Aires Camões |
|---|---|
| Přispěvatelé: | Universidade do Minho |
| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
Materials science
Carbonation 0211 other engineering and technologies General Physics and Astronomy 02 engineering and technology Fly ash Wetting-drying cycles Chloride 021105 building & construction medicine General Materials Science Composite material Curing (chemistry) Cement Science & Technology General Chemistry Pozzolan 021001 nanoscience & nanotechnology Mortar Cementitious 0210 nano-technology medicine.drug |
| Zdroj: | Matéria (Rio de Janeiro) v.23 n.3 2018 Matéria (Rio de Janeiro. Online) instacron:RLAM Malheiro, R, Camões, A, Meira, G, Amorim, M T, Castro-Gomes, J & Ferreira, R M 2018, ' Behaviour of cementitious matrices subjected to the combined action of chloride ions and carbonation ', Revista Materia, vol. 23, no. 3, e-12162 . https://doi.org/10.1590/S1517-707620180003.0496 Matéria (Rio de Janeiro), Volume: 23, Issue: 3, Article number: e12162, Published: 18 OCT 2018 CIÊNCIAVITAE Repositório Científico de Acesso Aberto de Portugal Repositório Científico de Acesso Aberto de Portugal (RCAAP) instacron:RCAAP |
| ISSN: | 1517-7076 |
| DOI: | 10.1590/S1517-707620180003.0496 |
| Popis: | Carbonation and chloride action are the two leading causes of degradation in reinforced concrete structures. Despite the combined action of these two mechanisms being a reality, there is little research on the effect of this combination in cementitious matrices. Furthermore, the incorporation of fly ash in cementitious matrices has been frequently used in order to make the matrix more resistant to the action of chlorides. On the other hand, it is known that Ca(OH)2 existing in the matrix is consumed by the pozzolanic reactions, which makes easier the carbonation front advance. Therefore, this paper presents a study of the behavior of cementitious matrices, with and without fly ash, subjected to the combined action of chlorides and carbonation. Two different kinds of mortars were produced: reference (only cement CEM I 42.5R) and fly ash mortar (40% replacement of cement). After curing, the specimens were subjected to three different wetting-drying cycles, considering NaCl solutions and CO2 atmospheres. Afterwards, chloride profiles and carbonation front were measured. Results show that carbonation has a direct influence on chloride penetration, decreasing it for cement mortars with 0% fly ash and increasing it for mortars with 40% cement replacement by fly ash. Moreover, the evolution of carbonation is also influenced by chloride presence, which decreases under the combined action. The authors thank the Foundation for Science and Technology (FCT) for supporting this research. The authors also thank the SECIL for making available cement used in this research and the CIMENTEIRA DO LOURO for providing the aggregates used. This work is co-financed by FEDER funds through the Competitively Factors Operational Programme - COMPETE and by national funds through FCT within the scope of the project POCI-01-0145-FEDER007136. info:eu-repo/semantics/publishedVersion |
| Databáze: | OpenAIRE |
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