Appropriate damping on seismic design analysis for inelastic response assessment of piping

配管弾塑性評価のための耐震解析で用いる適切な減衰

渡壁 智祥; 森下 正樹 

Watakabe, Tomoyoshi; Morishita, Masaki

現行の配管耐震設計規格の代替規定として、新たな事例規格が日本機械学会傘下の委員会において策定中である。本規格では、塑性による応答低減効果を見込んだ簡易解析を設計に取り入れることが検討されている。本研究では、簡易解析の適用性について解析的に検討した。応答スペクトル解析と応力係数による簡易計算に基づく現行設計解析に含まれる余裕を付加減衰の観点で定量的に評価した。

A new Code Case for seismic design of piping is now under development in the framework of JSME Nuclear Codes and Standards as an alternative rule to the current design rule. Simplified analysis with an additional damping taking the response reduction due to plasticity into account is now under consideration to incorporate the convenience in design. In this study, a series of analysis was made to see the adequacy of the simplified inelastic analysis. Design margins contained in the current design analysis method composed of response spectrum analysis and stress factors was quantitatively assessed in the view point of additional damping.