The structure in which radioactive substances are stored and handled must be earthquake resistant. We will be confirming radioactive shielding performance of reinforced concrete walls when cracks occur due to large earthquakes. In this study, we performed horizontal loading experiments to evaluate shielding performance of earthquake resisting walls and constructed a safety crack model. Next, the shielding calculation was done by using the crack model, and the shielding performance of the earthquake resisting wall was evaluated. As a result, if the structure is designed according to the standards outline for nuclear power related facility, and an earthquake causes cracks in an earthquake resisting wall, it was shown that if the thickness of the earthquake resisting wall was less than 80 cm, the decrease in shielding performance was very small, and that the radiation exposure on the general public and the employee was negligible.

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