報告書番号

O01

タイトル（和文）

高強度金網を用いた竜巻飛来物対策工の合理的な衝撃応答評価手法

タイトル（英文）

Rational Evaluation Method for Impact Response of Tornado Protection Structure using High Strength Wire Net

概要 （図表や脚注は「報告書全文」に掲載しております）

電気事業では、原子力発電所における竜巻飛来物防護対策の有望な工法の一つとして、風荷重や地震荷重の軽減が可能な防護ネットの採用を検討している。本研究では、対策工に適用可能な耐衝撃性能に富んだネット材の選定、ネット材料の最適な設置工法を決定した上で、対策工の耐衝撃性能を試験より確認し、設計に利用可能な吸収エネルギー性能、耐貫通性能、クリアランス等の衝撃応答評価手法を構築することを目的に、スクリーニング試験、高強度金網の基本性能評価手法の考案、自由落下する重錘を実規模大高強度金網に衝突させる自由落下衝突試験、小口径飛来物を用いた高速衝突試験を実施した。これら試験より得られた対策工の衝撃応答データを基に、対策工の衝撃応答挙動を評価する簡易応答評価手法と詳細応答評価手法の二つの評価手法を提案し、実験結果と比較することで、両手法の妥当性を示した。

概要 （英文）

A practical design of a tornado missile protection structure is becoming a technical key issue in order to meet the New Regulatory Requirements for a nuclear power plant in Japan. Utilization of a net structure is one of the options as realistic protection measures owing to the less severe wind and seismic loads. In this study, high strength wire net (protection net) was selected through material screening tests, and then three kinds of mechanical tests were carried out to establish an evaluation method for impact response of the net structure caused by tornado missiles with respect to the absorbed energy, maximum deformation, etc. At first, impact tensile tests of a piece of protection net were performed to obtain dynamic material properties to be used in a formula for limit value of energy absorption of the net. Secondly, free drop impact tests were conducted using two types of heavy weights (i.e., one is a circular cylinder; the other is with a nose of hollow square pipe). Thirdly, high speed impact tests using a small diameter missile were conducted. These results have allowed us to confirm not only the validity of the formula for impact response evaluation, but also good impact resistant performance of a protection net structure. Moreover, two evaluation methods (simplified and precise methods) for impact response of the structure were proposed. It was confirmed that these values derived from the evaluation methods were in good agreement with the experimental values, and that these methods were applicable to the evaluation of the impact response of this net structure.

報告者

キーワード