DETERMINATION OF FRACTAL DIMENSION IN CEMENT GELS BY PIXE

Two samples of ordinary Portland cement, one consisting of dry powder and the other of hydrated paste 28 days old, were bombarded with proto ns, resulting in proton-induced x-ray emission (PIXE). The x-ray yield was measured as a function of the exit angle and the differences betw een 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-ang le neutron scattering and nuclear magnetic resonance.