Pore size NMR imaging

Magnetic resonance imaging (MRI) experiments with industrial or civil engineering materials do not in general aim at determining more than water density distribution or profile, Nevertheless, it is fundamental to know more about their internal structure in relation to their macroscopic behaviour. Two techniques make possible such studies. They involve magnetic resonance imaging coupled with an analysis of respectively freezing and relaxation effects. These techniques do not have the usual magnetic resonance imaging resolution limitations. We present a mathematical treatment of data obtained by these techniques that directly provides spatial maps of the different moments of the pore size distribution. (C) 1998 Elsevier Science Inc.