A Required Condition of Thaumasite Formation in Marine Environments

In order to investigate the required conditions of thaumasite formation in marine environments, a series of experiments were carried out. The following factors were considered: cement and sand types, water/cement ratio (W/C), temperature, solution composition such as water, seawater, sulfate solution, and exchanging interval of solution. In the case of sulfate solution with a shorter exchange interval, typical external sulfate attack accompanying ettringite formation was observed at 5°C for higher W/C mortar. In the case of a longer exchange interval at 5°C, some differences were observed in the deteriorated texture depending on sand types for higher W/C mortar. Surface texture was pealed out when rectangular mortar specimens made of limestone sand were immersed in seawater and sulfate solution. In the deteriorated part, thaumasite was identified. The increase in pH by prolonging an exchanging interval is estimated as a reason for thaumasite formation. In actual marine environments, seawater is continuously exchanged and this reduces the possibility of thaumasite formation even for concrete containing calcite. Stagnant condition is much more dangerous for thaumasite sulfate attack.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/9780415593168
• Corporate Authors:

  CRC Press/Balkema

  P.O. Box 447
  2300 AK Leiden,   Netherlands 
• Authors:
  • Nozaki, T
  • Ogawa, S
  • Hirao, H
  • Kono, K
  • Yamada, K
• Conference:
  • Sixth International Conference on Concrete under Severe Conditions: Environment and Loading
  • Location: Merida Yucatan, Mexico
  • Date: 2010-6-7 to 2010-6-9
• Publication Date: 2010-7-5

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; Photos; References; Tables;
• Pagination: pp 85-90
• Monograph Title: Concrete under Severe Conditions: Environment and Loading. Proceedings of the 6th International Conference on Concrete Under Severe Conditions (CONSEC'10), Merida, Yucatan, Mexico, 7-9 June 2010

Subject/Index Terms

• TRT Terms: Corrosion; Seawater; Slag cement; Water cement ratio
• Candidate Terms: Seawater corrosion
• Uncontrolled Terms: Marine environment; Sulfate attack; Thaumasite
• Subject Areas: Bridges and other structures; Highways; Materials; I32: Concrete;

Filing Info

• Accession Number: 01373584
• Record Type: Publication
• ISBN: 9780415593168
• Files: TRIS
• Created Date: Jun 25 2012 9:39AM