纵向钢筋对配筋钢管混凝土柱性能的影响研究

RESEARCH ON EFFECT OF LONGITUDINAL REINFORCEMENT ON PERFORMANCE OF REINFORCED CONCRETE FILLED STEEL TUBULAR COLUMN

为了研究配筋钢管混凝土短柱中纵向钢筋(纵筋)的不同力学指标对构件基本力学性能的影响机制,进行了配置高性能带肋和普通光圆两种类别纵筋的短柱轴心受压试验。采用基于性能的比较研究方法,在对承载力、延性、变形、钢管和钢筋的应变分布以及破坏模式等方面进行综合比较分析后发现:配有两种类型纵筋的配筋钢管混凝土短柱的受力性能没有发生明显差别,纵筋强度的直接提高或形状上的改变并不能有效改善构件整体性能,而配有材质与钢管相近的普通光圆纵筋的构件更能表现出优越的力学性能。由此可得,纵筋形状不是影响构件力学性能的主要因素,配置力学指标与钢管相匹配的纵筋才能使纵筋材质得以充分利用、改善性能进而降低构件的制作成本。

In order to make clear the influencing mechanism of longitudinal reinforcement which has differed mechanical properties on basic mechanical performance of reinforced concrete filled steel tubular （R-CFST） short column, axial compression tests of R-CFST with high-performance ribbed bars or plain bars were performed. Employing performanee- based-comparative study method, a comprehensive analysis was carried out on member＇ s bearing capacity, ductility, deformability and failure mode, and strain distribution characteristics of steel tube and reinforcement, and conclusions were drawn as that the differences of longitudinal reinforcement did not cause significant changes in loading features of R-CFST short column, increasing the strength or changing the shape of longitudinal reinforcements still could not bring effective improvement to overall performance of the member, and R-CFSTs with longitudinal reinforcement of plain bars whose material quality was closer to steel tube exhibited more excellent mechanical properties. As a result, the shape of longitudinal reinforcements was not the main factor which affected the mechanical properties of member, and assembling longitudinal reinforcements in accordance with the material properties of steel tube could bring full-use of reinforcements, so as to improve the performance and then results in decreased construction cost.