本研究以實驗方式探討高強度中空複合構材撓曲扭轉行為，使用22支不同斷面配置之高強度中空複合構材進行彎矩試驗、扭矩試驗與反覆載重試驗，本研究主要探討的參數為不同組合載重配置、混凝土包覆厚度，斷面深寬比，並利用實驗結果探討上述參數與構件強度、韌性及消散能量之關係。
研究結果顯示高強度中空複合構材其彎矩強度進行疊加時，需考慮拉力筋應變硬化，可獲較準確結果；扭矩強度部份若依疊加方式計算，依推導公式所得者將高於實驗值。再者，高強度中空複合構材隨著斷面深寬比的增加，其強度衰減亦隨之增加，混凝土厚度影響不大。另勁度衰減率部份，高強度中空複合構材隨著混凝土厚度增加，其勁度衰減率亦隨之增大，惟深寬比之影響不大。就韌性容量而言，其則隨著混凝土厚度的增加而減少。

This study focuses on the torsional-flexural behavior of hollow composite member composed of encased steel tube and high-strength reinforced concrete. A series tests of composite members with various sectional compositions subjected to eccentric cyclic loading were conducted. Structural parameters concerned in the designs included thickness of concrete, loading combinations and the sectional aspect ratios (depth/width ratios).
Test results showed that the member’s flexural strength could be evaluated by the method of superposition, if the strain-hardening characteristics of longitudinal bars was concerned. Test results also showed that the strength deterioration rate of composite members increased when the sectional aspect ratio was increased. Stiffness degradation was found to be higher when the section was composed of larger concrete thickness. Energy dissipation evaluated from the test information indicated that the ductility of member decreased when the concrete thickness was increased.

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