Research output: Chapter in Book/Report/Conference proceeding › Conference contribution › Research › peer-review
Exposure of Portland-Limestone Cement – Metakaolin Paste to Cold Chloride-Sulfate Environment: NMR Spectroscopy Assessment of Structural Changes in Hydrated Phases and Relation to Chloride Ingress. / Sotiriadis, Konstantinos; Мазур, Антон Станиславович; Толстой, Петр Михайлович; Ševčík, R.
International RILEM Conference on Synergising Expertise towards Sustainability and Robustness of Cement-based Materials and Concrete Structures. Springer Nature, 2023. p. 966-973 (RILEM Bookseries; Vol. 44).Research output: Chapter in Book/Report/Conference proceeding › Conference contribution › Research › peer-review
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TY - GEN
T1 - Exposure of Portland-Limestone Cement – Metakaolin Paste to Cold Chloride-Sulfate Environment: NMR Spectroscopy Assessment of Structural Changes in Hydrated Phases and Relation to Chloride Ingress
AU - Sotiriadis, Konstantinos
AU - Мазур, Антон Станиславович
AU - Толстой, Петр Михайлович
AU - Ševčík, R.
PY - 2023
Y1 - 2023
N2 - The effect of sulfates on chloride ingress and microstructure in Portland-limestone cement – metakaolin paste was studied. Crystalline and amorphous phases were investigated with X-ray powder diffraction and solid-state nuclear magnetic resonance spectroscopy. Free chlorides were determined with ion chromatography. The influence of metakaolin on the microstructure and chloride binding was highlighted by comparing the material with pure Portland-limestone cement paste. The results showed that the high Al content in metakaolin increased the chloride binding ability of the binder and Al incorporation in the C‒S‒H phase. Close to the surface, metakaolin admixture contributed in greater polymerization of the silicate chains of C‒S‒H, while larger amounts of unreacted clinker were observed, compared to deeper parts. At higher depths, chlorides bound in the form of Friedel’s salt and free chlorides, were considerably reduced, attributed to refinement of the matrix. The presence of sulfates in the exposure solution affected chloride binding by inhibiting the formation of Friedel’s salt and increasing free chlorides in the pore solution. Moreover, sulfates decreased the polymerization of the silicate chains in the C‒S‒H of the Portland-limestone cement – metakaolin paste and reduced the hydration of clinker in pure Portland-limestone cement paste.
AB - The effect of sulfates on chloride ingress and microstructure in Portland-limestone cement – metakaolin paste was studied. Crystalline and amorphous phases were investigated with X-ray powder diffraction and solid-state nuclear magnetic resonance spectroscopy. Free chlorides were determined with ion chromatography. The influence of metakaolin on the microstructure and chloride binding was highlighted by comparing the material with pure Portland-limestone cement paste. The results showed that the high Al content in metakaolin increased the chloride binding ability of the binder and Al incorporation in the C‒S‒H phase. Close to the surface, metakaolin admixture contributed in greater polymerization of the silicate chains of C‒S‒H, while larger amounts of unreacted clinker were observed, compared to deeper parts. At higher depths, chlorides bound in the form of Friedel’s salt and free chlorides, were considerably reduced, attributed to refinement of the matrix. The presence of sulfates in the exposure solution affected chloride binding by inhibiting the formation of Friedel’s salt and increasing free chlorides in the pore solution. Moreover, sulfates decreased the polymerization of the silicate chains in the C‒S‒H of the Portland-limestone cement – metakaolin paste and reduced the hydration of clinker in pure Portland-limestone cement paste.
KW - Chloride Ingress
KW - Metakaolin
KW - NMR Spectroscopy
KW - Portland-limestone Cement
KW - Sulfate Attack
UR - https://www.mendeley.com/catalogue/ec537d87-bf08-3c7a-bcb0-8f59ae8fd262/
U2 - 10.1007/978-3-031-33187-9_88
DO - 10.1007/978-3-031-33187-9_88
M3 - Conference contribution
SN - 978-3-031-33186-2
T3 - RILEM Bookseries
SP - 966
EP - 973
BT - International RILEM Conference on Synergising Expertise towards Sustainability and Robustness of Cement-based Materials and Concrete Structures
PB - Springer Nature
T2 - The International RILEM Conference on Synergising expertise towards sustainability and robustness of cement-based materials and concrete structures
Y2 - 14 June 2023 through 16 June 2023
ER -
ID: 112449863