鋼筋混凝土為國內現今最普遍使用的建築材料，擁有成本低、耐久性高、防火性佳、隔音優良及易於維護等優點。配合潤弘精密所研發之「五螺箍」，「五螺箍」是由一個中心大螺箍與四個角落小螺箍共同交織而成。四個角落小螺箍不僅僅對矩形RC柱之四個角落的混凝土提供圍束，亦可對大螺箍提供有效的側向束制以減緩其外擴現象；此外，小螺箍也能固定角落主筋並提供其側向支撐。
本研究係針對於鋼絞線主筋鋼筋混凝土柱進行探討，為延續歐昱辰教授高強度混凝土柱及接續林光奕、王柄雄年年發箍筋柱之研究，試體設計係採規範限制之最小箍筋體積比，共六組大型試體進行反覆載重側推分析，分別為兩組傳統方箍筋與四組五螺箍；混凝土設計抗壓強度為分別為35、70 MPa；縱向主筋皆採用鋼絞線其設計強度為1860 MPa、剪力(橫向)鋼筋降伏強度設計皆為420 MPa，測試為採用不同軸力比，藉由不同之軸力比比較之間之行為差異性，其中也會穿插Ou、林光奕之試體進行比較，以便日後工程學界之應用與分析。

Reinforced Concrete is used for most building in Taiwan. This is due to the advantage on fire resistance, high durability, low-cost and easy maintenance.The 5-spiral cage is made of a big spiral at the center with four small spirals at each corner interwoven together. The four small spirals not only can provide confinement to the concrete at the four corners of the rectangular RC column but also can provide effective lateral confinement to the big spiral. Additionally, these small spirals can also provide lateral support to the longitudinal bars at the corners.
In this study, an experimental testing was conducted as the continuation of previous study (Ou and Lin; Ou et. al). Six half-scale double curvature columns were constructed and tested under the combination of cyclic loading and constant axial compression. The specified concrete compressive strength is 35、70 MPa.Longitudinal reinforced is seven-wired strand (1860MPa) and transverse (SD 420) reinforcement having specified yield strength 420 MPa were used,respectively.The key parameters considered in the experimental program were varian of axial compression and amount of shear reinforcement.Based on the experimental result, a set of high-strength reinforced concrete column are proposed.

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