Photon and Fast Neutron Transmission Parameters of Metakaolin Doped Concrete.

Abstract

Radiation-shielding properties of metakaolin doped concrete samples were investigated in this report. The gamma photon mass attenuation coefficients and exposure buildup factor of the samples were determined theoretically using WinXcom and EXABCal software respectively for the energy range of 15 keV - 15 MeV and fast neutron removal cross section for the concrete sample was evaluated. Results indicated that, oxides of silicon, aluminum, calcium and iron determined through the energy dispersive X-ray fluorescence spectrometric analysis constitute more than 85% of the chemical composition of the concrete samples. The oxides contribute 85.46, 86.47, 87.55, 88.75, and 86.15 % of the total chemical oxides in MK00, MK05, MK10, MK15, and MK20 respectively. Densities of the prepared MK doped concrete were in the range of 2.575-2.667 g/cm3. Compressive stress of prepared MK doped concretes increased consistently with the curing period for each concrete sample. CS grew from 8.71 -10.63, 8.84 - 10.83, 9.44 - 11.22, 10.89 - 11.53, and 10.76 - 11.43 MPa for MK00, MK05, MK10, MK15, and MK20 respectively as the period extends from 7 to 28 days. Mass attenuation coefficient decrease steadily with an increase in energy up to about 0.1 MeV and the decrease become smaller beyond this energy with increasing energy for all the mixtures. Fast neutron removal cross section results indicate that MK10 (0.07693 cm-1) has the highest value of ΣR followed by MK15 (0.07628 cm-1) and MK20 (0.07537 cm-1) while MK00 (0.07380 cm-1) and MK05 (0.07404 cm-1) have approximately the same value. It was found that MK10 concrete has the best gamma radiation and fast neutron shielding ability among the MK doped concrete under study.