Rapid Quantitative Identification of Thaumasite

Abstract:

To establish a quantitative identification method of thaumasite, internal doping method was used to accelerate thaumasite form of sulfate attack (TSA). A cement-limestone powder paste doped 10% of magnesium sulfate was immersed in water at (5±2) °C, while the blank was in 10% magnesium sulfate solution (by weight). Paste corrosion products were analyzed by infrared spectrum (IR), thermal analysis, nuclear magnetic resonance (NMR), and X-ray diffraction (XRD)/Rietveld refinement methods. The results show that the thaumasite formation was successfully accelerated by internal doping method. A lot of thaumasite formed after 6-15 months low temperature sulfate attack with gray mud-like material. IR analysis is able to be used to analysis thaumasite qualitatively, and Rietveld refinement was suitable to quantitative analysis of thaumasite. A rapid quantitative identification method of thaumasite including visual inspection, IR spectrum and XRD/Rietveld refinement was also established which will improve the accuracy and rapidness of TSAs research.

• Periodical: Materials Science Forum (Volumes 743-744)
• Pages: 186-192
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.743-744.186
• Online since: January 2013
• Authors: Chang Cheng Li, Yan Yao, Ling Wang
• Keywords: Infrared Spectrum, Internal Doping Method, Quantitative Analysis, Rietveld Refinement, Thaumasite

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