Strength and Flexural Rigidity of RC Columns under Biaxial Bending

雙軸彎曲鋼筋混凝土柱之強度與剛度分析

10.6377/JA.200406.0015

張雲妃(Yun-Fei Chang)；陳義宏(Yih-Houng Chen)；許茂雄(Maw-Shyong Sheu)

鋼筋混凝土柱 ； 雙軸變曲 ； 撓曲剛度 ； 全程曲線 ； RC column ； biaxial bending ； flexural rigidity ； full curve

建築學報

47期（2004 / 06 / 01）

15 - 34

英文

根據「平面保持平面」與「應變諧合」之假設，本文在烤慮鋼筋與混凝土材料受力破壞之上升段與下降段應力－應變全程曲線以及箍筋之圍束效應，利用簡單之靜力平衡條件，建立雙軸彎曲鋼筋混凝土柱斷面適用於任意載重階段之非線性聯立方程式，同時提出一簡單之演算法，處理圍束與非圍束並存以及異形斷面之數值求解方法。然後，改良現行規範之有效轉動慣量公式，做之適用於雙軸彎曲鋼筋混凝土柱上升段與下降段之載重－位移全程曲線。利用本文所發展之程式分析國內外四十支試驗柱之極限載重與七支試驗柱之載重－位移全程曲線，結果相當吻合，足以証明本文理論及演算法之準確性。最後，以常用三種斷面之設計輔助圖，提供雙軸彎曲RC柱實用分析資訊。3

This paper presents a rigorous method for performing the sectional analysis utilizing realistic stress-strain models for concreter and a modification of the effective moment of inertia, Ie, in the current ACI Code to predict the load-deflection curves of RC columns under biaxial bending at any monotonic loading stage including post-ultimate stage. To verify the accuracy, forty experimental ultimate strength data are compared with the analytical results. Furthermore, three numerical examples are illustrated to provide design/check aids such as three-dimensional failure surfaces, interaction diagrams and dimensionless load contours. Seven experimental load-deflection curves are compared with the analytical results. It is observed that if some parameters are redefined, the effective moment of inertia, Ie, in the current ACI Code for flexural members can be employed to predict the complete load-deflection behavior very well.

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