鋼骨鋼筋混凝土(SRC)複合式構件，為鋼筋混凝土和鋼骨合成之複合斷面，由於鋼骨具備良好的韌性，且鋼筋混凝土能提供鋼骨有效支撐，延緩鋼骨挫屈及挫屈後強度衰減的速率，因此，此種斷面乃有效的耐震設計。然而，在甚多橋樑設計中，由於地形地物的限制，必需採取非對稱之結構系統，由於結構物之質心和剛心位置不一，在地震力來臨時，此載重偏心距將引起彎矩和扭矩的聯合作用。目前有關鋼骨鋼筋混凝土之研究，大部份均著重於此類構件之承壓強度，梁柱行為，及梁柱接頭耐震行為，對於其受扭行為之相關資訊則甚缺乏。 本研究針對中空鋼骨鋼筋混凝土扭轉撓曲載重行為進行探討。從扭矩與彎矩之互制作用，探討不同斷面配置與載重偏心距對構件極限強度、勁度衰減、韌性和消能能力之影響。實驗結果顯示，構件之承載能力，因扭矩與彎矩之聯合作用而有顯著之影響。 Due to the interaction of steel tube and reinforced concrete of a composite section design, it is found that the reinforced concrete is capable of delaying the local buckling of encased steel tube. This composite design can be adequate for earthquake resistant purposes under compressive or flexural loading, however, the design performance may be susceptible when applied to constructions with unsymmetrical loading which induces torsional load. This study is focused on the flexural-torsional behavior of a composite design composed of reinforce concrete and encased steel tube. Width/depth ratio of cross sections and eccentricity ratio, were chosen as the main parameters for comparisons. Behavior among members' ultimate strength, ductility, stiffness deterioration and energy dissipation capacity were also studied. It is concluded that the members' performance is significantly influenced by the interaction between torsional loading and bending moment.
