原子力施設機器の耐震評価手法による結果影響調査

Influence of differences between seismic safety evaluation methods for equipment and piping of a nuclear facility

西田 明美  ; 飯垣 和彦 ; 沢 和弘

Nishida, Akemi; Iigaki, Kazuhiko; Sawa, Kazuhiro

本研究は、原子力施設の機器・配管等の耐震裕度評価に資するため、原子力施設機器の耐震評価手法の違いが評価結果に及ぼす影響を調査することを目的とする。入力地震動は、茨城県大洗地区を対象に作成した最大加速度7001100ガルの200波の入力地震動のうちの1波を選定した。床応答スペクトルを用いる従来法、多入力法、および、3次元モデルを用いた応答解析手法による耐震余裕評価を実施し、手法による差異をまとめた。複数の機器系統について評価を実施した結果、今回のモデルプラントの主要機器の場合、多入力法および3次元モデルを用いた応答解析手法による結果は従来法の約半分の応答となることを確認した。

The objective of this research was to investigate the influence of differences between methods for evaluating the seismic response of the equipment and piping of a nuclear facility. For the input ground motion, one wave was chosen from among 200 waves of input ground motions of maximum acceleration of 700-1100 cm/s created for the Oarai District of the Ibaraki Prefecture. Seismic safety evaluations were performed using the conventional method, which relies on floor response spectrum data, the multi-input method, and the analytical method using a three-dimensional building model. The differences between the three methods were summarized. The target equipment and piping system were cooling systems in a model plant. It was found that the response predicted by the multi-input method and the analytical method using three-dimensional building model were approximately half of the response predicted by the conventional method.