A pilot study has shown that with NMR it is feasible to measure the
chloride concentration profiles in concrete. These preliminary measurements
were performed at a magnetic field of 5 T. With support of the Dutch Technology
Foundation (STW) and the Netherlands School for Advanced Studies in Construction
the construction of a high-field NMR scanner ( for the studies on moisture
and ion transport in concrete has been started. This scanner uses
a 4.7 T 200 mm clear bore Oxford magnet with a Doty gradient insert.
With this machine is it should be possible to measure on cylindrical samples
with 40 mm diameter
A photo of 4.7 T magnet
With this machine we aim to measure quasi simultanously the moisture
and both the sodium (Na) and chloride (Cl) profiles. We therefor have constructed
a NMR set-up with 2 receiver which are operated by one computer.
A photo of the NMR receiver with additional computers