Determination of fractal dimension in cement gels by PIXE

Abstract

Two samples of ordinary Portland cement, one consisting of dry powder and the other of hydrated paste 28 days old, were bombarded witb protons, resulting in proton-induced x-ray emission (PIXE). The x-ray yield was measured as a function of the exit angle and the differences between the two samples were interpreted by the hypothesis that the pores of the hydrated cement gel form a fractal. The fractal dimension that was calculated is in good agreement with the values found by small-angle neutron scattering and nuclear magnetic resonance.

A remark on nano-particle stability of cement C-S-H gel

“…Some papers [27][28][29][30], based on the nuclear magnetic resonance (NMR), have indicated the fractal nature of C-S-H gel, as does the protoninduced X-ray emission (PIXE) [31] which recorded the fractal dimension of C-S-H gel in good agreement with the values determined by SANS [6] and NMR [32]. There are also some methods utilizing the fractal image analysis of the surface of cement materials.…”