Water absorption test accompanied by dynamic neutron radiography of gamma-irradiated cement samples

This study is focused on the experimental investigation of the effect of early-age gamma-ray irradiation on the permeability of cement samples. Five samples set were manufactured and irradiated at early age. The hydration process was stopped using acetone in the sample age of 15 hours. The effect of gamma-ray irradiation on cement samples permeability was investigated with the help of water absorption test accompanied by dynamic neutron radiography imaging. The calibration of water thickness was performed on wedge-shaped phantom sample. The fitted calibration function was used for quantification of absorbed water content in the investigated cement samples. The calculated values have good correlation with the measured values. From the calculated water distribution curves over the sample height it can be seen that water penetrates in the irradiated more than 8 hours sample slightly faster and deeper with comparison to the not irradiated sample, however the maximum water content is somewhat lower, these can be an indirect evidence of lower porosity of irradiated sample and consequently higher pore pressure due to reduction of pore diameter