Micropore size analysis in oil-well cement by proton nuclear relaxation

The durability of cement depends mainly on cement microstructure parameters such as pore size distribution. In this study, we have observed pore size distribution in a Class G oil-well cement immersed for 1 year in brine at T=293 K, P=105 Pa and in a down-hole condition at T=353 K, P=7.106 Pa by proton nuclear magnetic spin-lattice relaxation (1H-NMR). After 4 months of immersion at T=293 K, P=105 Pa, the distribution of discrete relaxation rates reveals the fractal feature of the pore size distribution, whereas after 1 year at T=353 K, P=7.106 Pa, a dispersed distribution is still observed.