椭圆形钢管混凝土长柱偏压力学性能研究

BEHAVIOUR OF ELLIPTICAL CONCRETE-FILLED STEEL TUBULAR LONG COLUMNS SUBJECTED TO ECCENTRIC COMPRESSION

利用有限元分析软件ABAQUS建立了椭圆形钢管混凝土长柱偏压力学性能分析的有限元模型,并对12个椭圆形钢管混凝土长柱的偏压试验结果与有限元模拟结果进行对比。结果表明:有限元计算与试验所得的荷载-挠度全过程曲线、承载力及破坏形态吻合较好。在此基础上对其受力过程中钢管及混凝土应力、应变分布情况进行分析,同时给出钢管与混凝土之间的相互作用,并对长细比、偏心距、材料强度、钢管壁厚等参数对长柱偏压极限承载力及荷载-柱中挠度曲线的影响进行比较。结果表明:椭圆形钢管混凝土长柱在H/2处发生侧向挠曲破坏,长细比、混凝土抗压强度、钢管壁厚及偏心距等参数对其力学性能影响显著,钢管屈服强度对其力学性能影响不明显。

A finite element analysis model of elliptical concrete-filled steel tubular （CFST） long columns subjected to eccentric compression is established using the finite element analysis software ABAQUS and the corresponding tests of 12 specimens are carried out .The results show the predicted relationship curves of load versus deflection in the middle column and damage modes are in good agreement with the measured results .The finite element analysis model is thus used to investigate the stress and strain distribution of each component and the interaction between the steel tube and the core concrete in the whole loading process .And then, the main parameters influencing the relationship curves of load versus deflection in the middle column such as slenderness ratio , material strength , steel tube wall thickness and eccentric distance are investigated .The results show the typical failure modes of these columns were the lateral overall bending at about mid-height, the slenderness ratio , the compressive strength of concrete , the steel tube wall thickness and the load eccentricity have obvious effects on their mechanical behavior , while the yield strength of steel tube has slight effect on their mechanical behavior .