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