组合T形截面钢管混凝土柱偏心受压试验研究

在分析各种异形钢管混凝土柱工程应用的基础上，提出组合T形截面钢管混凝土柱。考虑长细比、偏心距等参数的影响，设计制作18个组合T形钢管混凝土柱试件。通过偏心受压试验，对长细比16.0<λ≤28.8的组合T形钢管混凝土柱压弯性能进行研究，考察试件的破坏形态，实测试件的荷载-应变曲线和荷载-柱中挠度曲线，分析各参数对试件偏心受压力学性能的影响。通过试验数据回归分析，参考国内外相关规范，提出组合T形截面钢管混凝土柱偏心受压承载力计算公式。试验结果表明：偏心受压柱均为弯曲失稳破坏，长细比越大，弯曲破坏特征越明显；偏心距越大，试件极限承载力越低。研究表明，组合T形钢管混凝土柱的两个组成部分能很好地协同工作，力学性能较好；所提出的承载力计算公式可供工程设计参考。图10表3参8

Study on composite T-shaped concrete filled steel tubular columns under eccentric compression

Based on the summary of various types of special shaped concrete-filled steel tubular columns in practical application, composite T-shaped concrete-filled steel tubular column was presented in this paper. Eighteen composite T-shaped concrete-filled steel tubular columns were designed and manufactured with considering several experimental parameters such as the slenderness ratio and the eccentricity. Eccentric compression tests were carried out, and the mechanical behavior of composite T-shaped concrete-filled steel tubular columns with the slenderness ratio of 16<λ≤28.8 were investigated, focusing on the load-strain relationships, load-column deflection relationships, failure modes of the specimens, and the effects of different influencing parameters on the eccentric compression properties of the specimens. Based on the existing methods in both domestic and foreign codes, the practical design formula for the eccentric compression bearing capacity of composite T-shaped concrete-filled steel tubular columns was derived through the regression analysis of experimental data. The results show that the eccentric compression columns are dominated by flexural buckling, and the greater the slenderness ratio is, the more obvious the characteristic of flexural failure is. The studies show that the two parts of composite T-shaped concrete-filled steel tube column can work together very well with good mechanical properties. The formula could be valuable for engineering design.