鋼筋混凝土梁在撓曲、剪力與扭力組合載重下之行為

Behavior of Reinforced Concrete Beams Subjected to Combined Bending, Shear and Torsion

方一匡(I-Kuang Fang) ； 林廷駿(Tin-Juin Lin) ； 張簡建良(Jian-Ling Jean Chang)

《中國土木水利工程學刊》 24卷2期 (2012/06) Pp. 135-145

https://doi.org/10.6652/JoCICHE.201206_24(2).0004

摘要

本文旨在探討鋼筋混凝土梁在撓曲、剪力和扭力組合載重作用下之行為，同時驗證AASHTO-LRFD規範及ACI318-08規範中有關梁縱向鋼筋量規定之合理性。實驗工作部分共測試10根實心與空心矩形斷面梁，扭矩與彎矩（T/M）之比例分別為0、1/10、1/8。研究結果顯示，梁之破壞模式均為具有韌性之撓曲破壞，對空心斷面試體而言，T/M值由0增至1/8時，撓曲強度減少約15％，撓曲曲率韌性比減少高達74％。以Elfgren與Hsu之組合載重互制式預測試體之破壞載重有良好的關聯性。以AASHTO-LRFD規範及ACI1318-08規範設計梁之縱向鋼筋量時，設計值分別為實際值之1.36倍及1.26倍，亦即依前者設計之縱向鋼筋量較多。

關鍵字

鋼筋混凝土 ； AASHTO-LRFD規範 ； 扭力 ； 梁 ； 組合載重

並列摘要

The behavior of reinforced concrete beams subjected to combined bending, shear and torsion are presented. The requirements of flexural reinforcement according to AASHTO-LRFD and AC13 18-08 Codes are also discussed. Ten beam specimens with solid and hollow rectangular cross sections were tested. The ratios of torsional moment to bending moment (T/M) were 0, 1/10, and 1/8, respectively. Results showed that all beams failed in ductile flexure mode. As the T/M ratios increased from 0 to 1/8, the flexural strength decreased about 15% and the associated flexural curvature ductility decreased up to 74% in specimens with hollow section. Good correlation of failure loads was found between test results and interaction equation proposed by Elfgren and Hsu. The required amounts of longitudinal reinforcement according to AASHTO-LRFD and ACI318-08 Code are 1.36 and 1.26 times the actual values, respectively, i.e., more longitudinal reinforcement is needed using AASHTC code.

並列關鍵字

reinforced concrete ； AASHTO-LRFD ； torsion ； beam ； combined loads