Moisture Transport in Heated Concrete, as Studied by NMR, and its Consequences for Fire Spalling

During the past 30 years concrete has developed enormously in both strength and durability. A drawback to these improvements is the increased risk of explosive spalling in case of fire. The moisture inside the concrete plays an important role in the spalling mechanism. In order to study the moisture migration inside concrete during intense heating, a dedicated nuclear magnetic resonance setup was built. This setup can be placed inside a 1.5-T MRI scanner. With this setup, 1-D moisture profiles can be measured while the concrete sample is heated up to 250 °C. Besides concrete, measurements were performed on fired-clay brick and calcium-silicate brick. Results show that water inside the concrete sample is superheated to a temperature of 170 °C, resulting in increased pressure inside the concrete. A model was developed to predict the movement of the observed drying front.

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  • Supplemental Notes:
    • Abstract reprinted with permission from Elsevier
  • Authors:
    • van der Heijden, G H A
    • van Bijnen, R M W
    • Pel, L
    • Huinink, H P
  • Publication Date: 2007-6

Language

  • English

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Filing Info

  • Accession Number: 01054293
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jul 25 2007 6:47PM