不同加载角度下多室T形截面钢管混凝土柱偏压性能研究  

Eccentric compressive behavior of multi-cell T-shaped concrete-filled steel tubular columns at different loading angles

作　　者：郑永乾[1] 梁王赓 林益豪 ZHENG Yongqian;LIANG Wanggeng;LIN Yihao(Fujian Provincial Key Laboratory of Advanced Technology and Informatization in Civil Engineering,Fujian University of Technology,Fuzhou 350118,China)

机构地区：[1]福建工程学院福建省土木工程新技术与信息化重点实验室,福建福州350118

出　　处：《建筑结构学报》2022年第12期145-156,共12页Journal of Building Structures

基　　金：国家自然科学基金项目(51678151);福建省自然科学基金项目(2019J01780)。

摘　　要：多室T形钢管混凝土柱作为建筑结构的边柱,会受到不同角度荷载的作用。为研究不同加载角度下多室T形截面钢管混凝土柱的受力性能,进行了7个多室T形截面钢管混凝土柱试件和1个无肋对比试件的偏压性能试验研究,试验主要参数包括加载角度(45°、90°、135°和180°)、荷载偏心率(0、0.25和0.5)和长细比(31.5和41.9)。结果表明:采用多室截面能够有效延缓T形截面钢管混凝土柱的局部屈曲,承载力比无肋试件提高10.8%;加载角度135°对应的承载力最大,180°对应的承载力最小,最大相差17.3%;随着荷载偏心率或构件长细比的增加,柱峰值荷载下降,峰值荷载对应的柱中挠度增加。采用有限元软件建立了不同加载角度下多室T形截面钢管混凝土柱偏压的有限元模型,有限元计算结果与试验结果吻合良好。在参数分析基础上,获得了不同加载角度下多室T形截面钢管混凝土柱稳定系数和相对轴力-弯矩相关曲线简化计算方法,简化计算结果得到了试验结果的验证。Multi-cell T-shaped concrete-filled steel tubular(CFST) columns are often subjected to loads from different loading angles as the edge columns in building structures. In order to study the mechanical behavior of multi-cell T-shaped CFST columns at different loading angles, seven multi-cell T-shaped CFST specimens and one reference specimen were tested under eccentric compression. The main parameters of the tests were the loading angle(45°, 90°, 135° and 180°), load eccentricity ratio(0, 0.25 and 0.5), and slenderness ratio(31.5 and 41.9). The results show that the use of multi-cell cross-section can effectively delay the local buckling of T-shaped CFST columns, and the load bearing capacity can be improved by 10.8% compared with the unstiffened column. The load bearing capacity is the highest at a loading angle of 135° and the lowest at a loading angle of 180° with a maximum deviation of up to 17.3%. With the increase of load eccentricity ratio or slenderness ratio, the peak load and its corresponding mid-height deflection increase. A finite element(FE) software was used to establish the nonlinear model of multi-cell T-shaped CFST columns under eccentric compression at different loading angles. The FE results are in good agreement with the experimental results. Based on the parametric analysis, practical design methods for the stability coefficient and the relative axial force-bending moment interaction curve of the multi-cell T-shaped CFST columns at different loading angles were obtained. The simplified prediction results were verified by the test results.

关 键 词：T形截面钢管混凝土柱 多室截面 加载角度 偏压性能 稳定系数 轴力-弯矩相关曲线 

分 类 号：TU398.903[建筑科学—结构工程] TU311.41