Thaumasite formation in a tunnel of Bapanxia Dam in Western China
Abstract
A site investigation and sampling was carried out on a sulfate-attacked concrete structure in Bapanxia Hydraulic Power Plant in Western China. The concrete had been exposed to ground water containing substantial concentrations of salts (SO{sub 4} {sup 2-}, CO{sub 3} {sup 2-} and Cl{sup -}) for about 6 years and was analyzed with X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), laser-Raman spectroscopy and Fourier transform infrared (FTIR) spectroscopy. It is shown that a white mushy mixture consisting of thaumasite, ettringite, gypsum and calcite is present in the residual concrete. This paper reports the first instance of the thaumasite form of sulfate attack of concrete in China.
- Authors:
- Key Laboratory of Silicate Materials Science and Engineering of Ministry of Education, Wuhan University of Technology, Wuhan 430070, (China)
- Key Laboratory of Silicate Materials Science and Engineering of Ministry of Education, Wuhan University of Technology, Wuhan 430070, (China). E-mail: xjgao2002@yahoo.com.cn
- CMRU, Department of Civil and Structural Engineering, University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom)
- Department of Engineering Materials, University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom)
- Publication Date:
- OSTI Identifier:
- 20793284
- Resource Type:
- Journal Article
- Resource Relation:
- Journal Name: Cement and Concrete Research; Journal Volume: 36; Journal Issue: 4; Other Information: DOI: 10.1016/j.cemconres.2005.10.011; PII: S0008-8846(05)00233-4; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE; CALCITE; CHINA; CONCRETES; DAMS; FOURIER TRANSFORMATION; GROUND WATER; GYPSUM; INFRARED SPECTRA; PYRAZOLINES; RAMAN SPECTROSCOPY; SCANNING ELECTRON MICROSCOPY; SULFATES; TUNNELS; X-RAY DIFFRACTION; X-RAY SPECTROSCOPY
Citation Formats
Ma Baoguo, Gao Xiaojian, Byars, Ewan A., and Zhou Qizhi. Thaumasite formation in a tunnel of Bapanxia Dam in Western China. United States: N. p., 2006.
Web. doi:10.1016/J.CEMCONRES.2005.1.
Ma Baoguo, Gao Xiaojian, Byars, Ewan A., & Zhou Qizhi. Thaumasite formation in a tunnel of Bapanxia Dam in Western China. United States. doi:10.1016/J.CEMCONRES.2005.1.
Ma Baoguo, Gao Xiaojian, Byars, Ewan A., and Zhou Qizhi. Sat .
"Thaumasite formation in a tunnel of Bapanxia Dam in Western China". United States.
doi:10.1016/J.CEMCONRES.2005.1.
@article{osti_20793284,
title = {Thaumasite formation in a tunnel of Bapanxia Dam in Western China},
author = {Ma Baoguo and Gao Xiaojian and Byars, Ewan A. and Zhou Qizhi},
abstractNote = {A site investigation and sampling was carried out on a sulfate-attacked concrete structure in Bapanxia Hydraulic Power Plant in Western China. The concrete had been exposed to ground water containing substantial concentrations of salts (SO{sub 4} {sup 2-}, CO{sub 3} {sup 2-} and Cl{sup -}) for about 6 years and was analyzed with X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), laser-Raman spectroscopy and Fourier transform infrared (FTIR) spectroscopy. It is shown that a white mushy mixture consisting of thaumasite, ettringite, gypsum and calcite is present in the residual concrete. This paper reports the first instance of the thaumasite form of sulfate attack of concrete in China.},
doi = {10.1016/J.CEMCONRES.2005.1},
journal = {Cement and Concrete Research},
number = 4,
volume = 36,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
-
According to microanalytical investigations, it is shown that the concrete of Yongan Dam is deteriorated due to the thaumasite form of sulfate attack (TSA). Analysis results of scanning electron microscopy (SEM), Energy Disperse X-ray (EDX) and X-ray Diffraction (XRD) are supported by the analysis of the concrete composition and the geographical conditions of the dam.
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