Concrete thawing studied by single-point ramped imaging

Solid State Nucl Magn Reson. 1997 Dec;10(1-2):1-8. doi: 10.1016/s0926-2040(97)00071-4.

Abstract

A series of two-dimensional images of proton distribution in a hardened concrete sample has been obtained during the thawing process (from -50 degrees C up to 11 degrees C). The SPRITE sequence is optimal for this study given the characteristic short relaxation times of water in this porous media (T2* < 200 micros and T1 < 3.6 ms). The relaxation parameters of the sample were determined in order to optimize the time efficiency of the sequence, permitting a 4-scan 64 x 64 acquisition in under 3 min. The image acquisition is fast on the time scale of the temperature evolution of the specimen. The frozen water distribution is quantified through a position based study of the image contrast. A multiple point acquisition method is presented and the signal sensitivity improvement is discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Image Processing, Computer-Assisted / methods
  • Magnetic Resonance Imaging / methods*
  • Water / analysis

Substances

  • Water