Users may download and print one copy of any publication from the public portal for the purpose of private study or research. You may not further distribute the material or use it for any profit-making activity or commercial gain You may freely distribute the URL identifying the publication in the public portal If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.
Investigations of synthetic magnesium silicate hydrate (M-S-H) samples have shown that M-S-H aged for 1 year can exhibit variable compositions with molar Mg/Si ratios in the range 0.7 ≤ Mg/Si ≤ 1.5. At lower Mg/Si ratio, additional silica is present whereas brucite is observed for Mg/Si ≥1.3. FT-IR and 29 Si NMR data reveal a high degree of silicate polymerisation, indicating the formation of silicate sheets. TGA shows the presence of bound water and of hydroxyl groups bound to Mg and as silanol groups in the M-S-H, in accord with 29 Si{ 1 H}CP/MAS and high-speed 1 H NMR measurements. Raman and XRD data suggest that the M-S-H structure is related to a disordered talc precursor at low Mg/Si and to a serpentine precursor at high Mg/Si ratio. Solubility products for M-S-H phases were calculated on basis of the compositions of the aqueous solutions and a solid solution model was suggested.
Users may download and print one copy of any publication from the public portal for the purpose of private study or research. You may not further distribute the material or use it for any profit-making activity or commercial gain You may freely distribute the URL identifying the publication in the public portal If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.
Thermogravimetric analysis (TGA), powder X-ray diffraction (XRD) and thermodynamic modelling have been used to obtain Friedel's salt profiles for saturated mortar cylinders exposed to a 2.8 M NaCl solution. Comparison of the measured Friedel's salt profiles with the total chloride profiles indicates that only a minor part of the chloride ions is bound in Friedel's in the studied Portland cement (P) and limestone blended (L) cement. The chloride binding capacity with respect to the formation of Friedel's salt by consumption of monocarbonate is reached for the P and L mortars, where only a fraction of about 20 % of the amount of C3A is found to contribute to formation of Friedel's salt. Higher amounts of Friedel's salt are formed in the metakaolin containing mortars. However, the limited chloride ingress depths prevent quantification of the potential full chloride binding capacity of Friedel's salt in these mortars.The measured amounts of Friedel's salt by TGA and the portlandite profiles show that the maximum amount of Friedel's salt is found in the region with limited leaching of calcium, which is in good agreement with the predicted Friedel's salt profiles.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.