完全合成SRC梁之強度與耐震設計

Flexural Strength and Seismic Design of SRC Beam Sections with Complete Composite Action

本文建立一符合完全合成條件之SRC 梁撓曲強度設計法，稱之為MMC （Multiple MomentComponents ）設計法。相對於現行之強度疊加法，MMC 法不但可以節省可觀的材料使用量，而且還可以對斷面之韌性有良好的掌握。MMC 法不經過疊代的過程，就可求得所需鋼筋量，容易應用於工程實務。本文也發現，以MMC 法進行斷面設計，不但可以保持斷面於混凝土保護層開始碎裂時之曲率延展比不小於2 ，若加上箍筋間距不大於8 倍主筋直徑之限制，則該斷面即可發展出不小於9 的變形極限曲率延展比，可以滿足一般耐震所需。此外本文還建立SRC 梁斷面曲率延展比之關係式，可用以評估SRC 梁斷面之曲率延展比。

A rational flexural strength design method, which fulfills the assumption of complete composite action, was developed for steel reinforced concrete (SRC) beam sections. The proposed design method, which is named as MMC method, is fairly simple and accurate. Therefore, sections designed according to MMC method are more economical then those designed according to the strength superposition method. For those sections designed according to MMC Method, a minimum ductility ratio of 2, at the spalling of the cover concrete, can be reached. With the limitation of hoop spacing no greater than 8 times the diameter of main reinforcing bar, the designed sections are able to reach an ultimate ductility ratio of at least 9. Which is consider adequate for ductility design of earthquake-resistant structures. In addition, empirical formulas were established to evaluate the curvature ductility ratio of SRC sections.