Moisture transport in heated concrete, as studied by NMR, and its consequences for fire spalling
- Transport in Permeable Media, Eindhoven University of Technology, Department of Applied physics, 5600 MB Eindhoven (Netherlands)
During the past 30 years concrete has developed enormously in both strength and durability. A drawback of 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 (NMR) setup was built. This setup can be placed inside a 1.5-T MRI scanner. With this setup one-dimensional moisture profiles can be measured while the concrete sample is heated up to 250 deg. C. Besides concrete, measurements were performed on fired-clay brick and calcium-silicate brick. The results show that water inside the concrete sample is superheated to a temperature of 170 deg. C, which results in an increased pressure inside the concrete. A model was developed to predict the movement of the observed drying front.
- OSTI ID:
- 20995391
- Journal Information:
- Cement and Concrete Research, Vol. 37, Issue 6; Other Information: DOI: 10.1016/j.cemconres.2007.03.004; PII: S0008-8846(07)00072-5; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0008-8846
- Country of Publication:
- United States
- Language:
- English
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