STUDIES ON FORMULATION OF R/C COLUMN UNDER BIAXIAL BENDING

通过试验研究，阐明了横向钢筋对钢筋混凝土柱强度和延性的改善作用。60个试件的偏心加载试验结果表明，间距小、掺量充足的围筋对柱具有显著的延性。结果表明，围筋足够含量大于1.0，本文定义为围筋（体积）比与纵筋（面积）比的围筋比。本研究的主要目的是寻找双轴弯曲下柱的极限强度和延性最适用的计算公式。从试验与分析结果的对比来看，Ramamurthy提出的双轴弯矩公式是最适用的，但没有关于延性的公式。为此，提出了新的计算公式，并通过大尺度模型验证了其适用性。

This study experimentally clarifies how the strength and ductility of reinforced concrete columns are improved by transversery confining reinforcements.The results of eccentrically loaded test of 60 specimens indicate that the confining reinforcement with close spacing and enough content gives a remarkable ductility to the column. It is shown that the enough content of confining reinforce- ment is more than the value of 1.0 which is defined , in this study,as the confining ratio of confining reinforcement(voume) ratio to the longitudinal reinforcement(area) ratio.Main object of this study was to find the most spplicable formulas for the ultimate strenght and ductility of the column under biaxial bending.From the results of the comparison betwen expriments and analysis, it was found that the formula proposed by Ramamurthy for biaxial bending moments was tghe most applicable one,but th was no formula for ductility. Therefore,new formulas were proposed and examined the applicablility by large scale models.