[1C14-18] Concrete 3

[1C15] Study on the Radionuclide Contamination Mechanisms of Concrete and the Estimation of Distribution of Radionuclides

(22)Different penetration behaviors of Cs and Sr in cracked concrete

Norio Muranaka², *Kazuo Yamada¹, Hideyuki Hokora³, Yasumasa Tojo², Ippei Maruyama⁴ (1. NIES, 2. Hokkaido Univ., 3. Taiheiyo Consultant, 4. U. Tokyo)

Keywords:Cs, Sr, penetration depth, crack, concrete

In the Fukushima Daiichi Nuclear Power Plant, where the accident occurred, it is necessary to know the penetration depth of Cs and Sr from the viewpoint of radiation exposure in order to evaluate the amount of radioactive contamination of the huge amount of concrete. Assuming that cracks larger than 0.2 mm have been repaired, the effect of cracks smaller than about 0.3 mm on the penetration depth was evaluated by autoradiography through immersion experiments considering the composition of contaminated water after the accident. The results showed that the penetration of Cs and Sr was similar in areas without cracks, but Sr penetration was faster in cracked areas.