方锥形钢管混凝土长柱工作机理分析

BEHAVIOUR OF SQUARE TAPERED CONCRETE-FILLED STEEL TUBULAR LONG COLUMNS

利用有限元分析软件ABAQUS建立方锥形钢管混凝土长柱力学性能分析的三维实体有限元计算模型,并进行相应的试验研究。有限元计算与试验所得的荷载-3H/4挠度曲线、承载力及破坏形态吻合较好。在此基础上,分析方锥形钢管混凝土长柱中钢管和混凝土的应力、应变分布情况以及钢管与混凝土之间的组合作用,并比较长细比、偏心距、锥度等参数对方锥形钢管混凝土长柱极限承载力及荷载-3H/4挠度曲线的影响。结果表明:方锥形钢管混凝土长柱在3H/4处发生倾向挠曲破坏,长细比、锥度、偏心距、混凝土抗压强度及钢管壁厚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 three-dimensional finite element analysis model for square tapered concrete-filled steel tubular long columns subjected to longitudinal compression is developed and the corresponding tests are conducted .The predicted relationship curves of load versus 3/4 height deflection , bearing capacities and failure modes have good agreements with the tested results .Based on the finite element analysis , stress and strain distribution in the whole loading process is analyzed , and interaction between steel tube and concrete is put forward .The influences of the main parameters such as slenderness ratio, eccentricity, tapered angle, have been analyzed on the ultimate loads and the relationship curves of load versus 3/4 height deflection of square tapered concrete-filled steel tubular long columns .The results show the typical failure modes of these columns were the lateral overall bending at about 3/4 height, the slenderness ratio, the tapered angle , the load eccentricity , the compressive strength of concrete and the steel tube wall thickness have obvious effects on their mechanical behavior , while the yield strength of steel tube has sight effect on their mechanical behavior .