The present paper discuses on a ductility factor of braces installed in longitudinal direction of school sport halls. Based on the result of the elasto-plasitc dynamic analysis depending on varying input levels, the ductility index and Ds factor are re-studied. As numerical parameters, yield shear coefficient of braces on substructure, capacity limit deformation of braces and types of ground site are considered, and their effects on the ductility index are investigated. Furthermore, the method of estimation for maximum deformation of braces and ductility index is proposed using an absorbed energy principle, and the validity of the proposal method is proven comparing the responses of the dynamic response analysis with those based on the proposed method.%本研究では，桁面に引張プレースを有する体育館を想定し，弾塑性応答解析より地震動強さんと桁面ブレースの塑性率の関係を分析し，桁面プレースの限界変形を表す塑性率μ_(cr)＝2，4，8，12に対応した靭性指標Fを求めた。また，桁面プレースの降伏層せん断力係数（C_y＝0.3，0.4，0.5）や地盤種別（第1種地盤，第2種地盤，第3種地盤）が靭性指標Fに与える影響を分析した。さらに，エネルギー法を用いた靭性指標の推定法を提案し，その有効性を検討した。得られた結論を以下に要約する。
展开▼
