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Advanced Rietveld refinement and SEM analysis of tobermorite in chemically diverse autoclaved aerated concrete

Published online by Cambridge University Press:  11 March 2019

J. Schreiner*
Affiliation:
University of Erlangen-Nuremberg, GeoZentrum Nordbayern, Mineralogy, Schlossgarten 5a, 91054 Erlangen, Germany
F. Goetz-Neunhoeffer
Affiliation:
University of Erlangen-Nuremberg, GeoZentrum Nordbayern, Mineralogy, Schlossgarten 5a, 91054 Erlangen, Germany
J. Neubauer
Affiliation:
University of Erlangen-Nuremberg, GeoZentrum Nordbayern, Mineralogy, Schlossgarten 5a, 91054 Erlangen, Germany
S. Volkmann
Affiliation:
Rodgauer Baustoffwerke GmbH & Co. KG, Am Opel-Prüffeld 3, 63110 Rodgau-Dudenhofen, Germany
S. Bergold
Affiliation:
Schlenk Metallic Pigments GmbH, Barnsdorfer Hauptstr. 5, 91154 Roth, Germany
R. Webler
Affiliation:
Schlenk Metallic Pigments GmbH, Barnsdorfer Hauptstr. 5, 91154 Roth, Germany
D. Jansen
Affiliation:
University of Erlangen-Nuremberg, GeoZentrum Nordbayern, Mineralogy, Schlossgarten 5a, 91054 Erlangen, Germany
*
a)Author to whom correspondence should be addressed. Electronic mail: juergen.js.schreiner@fau.de; daniel.jansen@fau.de

Abstract

Changes of structural properties of tobermorite in autoclaved aerated concrete (AAC) for various compositions were characterized and the disadvantages of SEM analysis in this context are discussed. The influence of variations in the chemical composition of raw materials on lattice parameters, morphology and domain sizes of tobermorite was investigated by XRD and for comparison by SEM analysis. Particularly the effect of substitution by Al3+ and (SO4)2− in tobermorite structure was examined. The dimensions of coherently scattering domains were calculated based on the refinement of anisotropic peak broadening of tobermorite in XRD diffractograms using a Rietveld compatible approach. No effect of (SO4)2− on the domain sizes and lattice parameters of tobermorite could be observed. The amount of anhydrite detected by quantitative XRD analysis indicates that all of the available (SO4)2− is present as anhydrite. Lath-like shapes of domains and a larger c parameter are calculated whenever Al3+ is incorporated in a considerable amount. Formation of katoite can be observed very clearly in SEM micrographs whenever the amount of available Al3+ exceeds a distinct value in the dry mix. The effect of Al3+ and (SO4)2− on tobermorite morphology could not be observed clearly by SEM analysis in AAC samples.

Type
Technical Article
Copyright
Copyright © International Centre for Diffraction Data 2019 

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References

Bailey, S. W. (1969). “Refinement of an intermediate microcline structure,” Am. Miner. 54, 15401545.Google Scholar
Bartl, H. (1969). “Roentgen-Einkristalluntersuchungen an (Ca O)3 (Al2 O3) (H2 O)6 und an (Ca O)12 (Al2 O3)7 (H2 O), neuer Vorschlag zur (Ca O)12 (Al2 O3)7-Struktur,” Neues Jahrb. Fuer Mineral. Monatshefte. 1969, 404413.Google Scholar
Bergmans, J., Nielsen, P., Snellings, R., and Broos, K. (2016). “Recycling of autoclaved aerated concrete in floor screeds: sulfate leaching reduction by ettringite formation,” Constr. Build. Mater. 111, 914.Google Scholar
Biagioni, C., Bonaccorsi, E., Lezzerini, M., and Merlino, S. (2016). “Thermal behaviour of Al-rich tobermorite,” Eur. J. Mineral. 28, 2332.Google Scholar
Brigatti, M. F., Lugli, C., Poppi, L., Foord, E. E., and Kile, D. E. (2000). “Crystal chemical variations in Li- and Fe-rich micas from Pikes Peak batholith (central Colorado),” Am. Mineral. 85, 12751286.Google Scholar
Cole, W. F., and Lancucki, C. J. (1974). “A refinement of the crystal structure of gypsum CaSO4.2H20,” Acta Crystallogr. B30, 921929.Google Scholar
Ectors, D., Goetz-Neunhoeffer, F., and Neubauer, J. (2015). “A generalized geometric approach to anisotropic peak broadening due to domain morphology,” J. Appl. Crystallogr. 48, 189194.Google Scholar
Hamid, S. A. (1981). “The crystal structure of the 11 Å natural tobermorite Ca2.25[Si3O7.5(OH)1.5]1H2O,” Zeitschrift Fuer Krist. – New Cryst. Struct. 154, 189198.Google Scholar
Hara, N., and Inoue, N. (1980). “Thermal behaviour of 11 Å tobermorite and its lattice parameters,” Cem. Concr. Res. 10, 5360.Google Scholar
Hughes, J. M., and Drexler, J. W. (1991). “Cation substitution in the apatite tetrahedral site: crystal structures of type hydroxylellestadite and type fermorite,” Neues Jahrb. Fuer Mineral. 1991, 327336.Google Scholar
Jackson, M. D., Chae, S. R., Mulcahy, S. R., Meral, C., Taylor, R., Li, P., Emwas, A. H., Moon, J., Yoon, S., Vola, G., Wenk, H. R., and Monteiro, P. J. M. (2012). “Unlocking the secrets of Al-tobermorite in Roman seawater concrete,” Am. Mineral. 98, 16691687.Google Scholar
Jansen, D., Goetz-Neunhoeffer, F., Stabler, C., and Neubauer, J. (2011). “A remastered external standard method applied to the quantification of early OPC hydration,” Cem. Concr. Res. 41, 602608.Google Scholar
Kirfel, A., and Will, G. (1980). “Charge density in anhydrite, CaSO4, from X-ray and neutron diffraction measurements,” Acta Crystallogr. Sect. B Struct. Crystallogr. Cryst. Chem. 36, 28812890.Google Scholar
Koutný, O., Opravil, T., and Pořízka, J. (2014). “Application of metakaoline in autoclaved aerated concrete technology,” Adv. Mater. Res. 1000, 174177.Google Scholar
Le Page, Y., and Donnay, G. (1976). “Refinement of the crystal structure of low-quartz,” Acta Crystallogr. Sect. B. 32, 24562459.Google Scholar
Małaszkiewicz, D., and Chojnowski, J. (2017). “Influence of addition of calcium sulfate dihydrate on drying of autoclaved aerated concrete,” Open Eng. 7, 273278.Google Scholar
Maslen, E. N., Streltsov, V. A., Streltsova, N. R., and Ishizawa, N. (1995). “Electron density and optical anisotropy in rhombohedral carbonates. III. Synchrotron Xray studies of CaCO3, MgCO3 and MnCO3,” Acta Crystallogr. Sect. B. 51, 929939.Google Scholar
Matsui, K., Kikuma, J., Tsunashima, M., Ishikawa, T., Matsuno, S., Ogawa, A., and Sato, M. (2011). “In situ time-resolved X-ray diffraction of tobermorite formation in autoclaved aerated concrete: influence of silica source reactivity and Al addition,” Cem. Concr. Res. 41, 510519.Google Scholar
Matsushita, F., Aono, Y., and Shibata, S. (2005). “Expansion and shrinkage behavior of green cake of Autoclaved Aerated Concrete,” Autoclaved Aerated Concrete – Innovation and Development: Proceedings of the 4th International Conference on Autoclaved Aerated Concrete, Kingston, UK, 8–9 September 2005, Vol. pp. 101108. CRC Press.Google Scholar
Merlino, S., Bonaccorsi, E., and Armbruster, T. (2000). “The real structures of clinotobermorite and tobermorite 9 Å: OD character, polytypes, and structural relationships,” Eur. J. Mineral. 12, 411429.Google Scholar
Mostafa, N. Y. (2005). “Influence of air-cooled slag on physicochemical properties of autoclaved aerated concrete,” Cem. Concr. Res. 35, 13491357.Google Scholar
Mostafa, N. Y., Shaltout, A. A., Omar, H., and Abo-El-Enein, S. A. (2009). “Hydrothermal synthesis and characterization of aluminium and sulfate substituted 1.1 nm tobermorites,” J. Alloys Compd. 467, 332337.Google Scholar
Rietveld, H. M. (1969). “A profile refinement method for nuclear and magnetic structures,” J. Appl. Crystallogr. 2, 6571.Google Scholar
Sauman, Z. (1972). “Influence of SO4 2– ions on the formation of 11 Å tobermorite,” Proceedings of the 2nd International Symposium on Science and Research in Silicate Chemistry, 2539.Google Scholar
Schreiner, J., Jansen, D., Ectors, D., Goetz-Neunhoeffer, F., Neubauer, J., and Volkmann, S. (2018). “New analytical possibilities for monitoring the phase development during the production of autoclaved aerated concrete,” Cem. Concr. Res. 107, 247252.Google Scholar
Skawinska, A., Owsiak, Z., Baran, T., and Hernik, K. (2017). “The influence of halloysite addition on tobermorite formation in CaO and quartz mix under hydrothermal conditions,” Cem. Wapno Bet. 17, 426434.Google Scholar
Triloki, , Garg, P., Rai, R., and Singh, B. K. (2014). “Structural characterization of as-deposited cesium iodide films studied by X-ray diffraction and transmission electron microscopy techniques,” Nucl. Instruments Methods Phys. Res. Sect. A Accel. Spectrometers, Detect. Assoc. Equip. 736, 128134.Google Scholar
Ungár, T., Tichy, G., Gubicza, J., and Hellmig, R. J. (2005). “Correlation between subgrains and coherently scattering domains,” Powder Diffr. 20, 366375.Google Scholar
Wang, Z., Ma, S., Zheng, S., and Wang, X. (2017). “Incorporation of Al and Na in Hydrothermally Synthesized Tobermorite,” J. Am. Ceram. Soc. 100, 792799.Google Scholar
Yang, T. (2006). “AFM study of the interactions between moisture and the surface of cementitious materials,” Dr. Thesis. 14, 3941.Google Scholar
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