【作者】 张迎春；

【导师】 李斌；

【作者基本信息】 内蒙古科技大学 ， 结构工程， 2008， 硕士

【摘要】 方钢管混凝土柱承载力高、延性好、施工速度快,同时具有外形整洁美观、节点相贯简单、构件连接方便等优点,在工程实践中得到了越来越广泛的应用,但是方钢管对混凝土的约束效果不显著,柱的承载力提高有限。针对方钢管混凝土柱的这一缺点,作者设计了一种新型的组合方钢管混凝土柱,从试验和理论两方面深入地研究了此种组合柱轴心受压时的力学性能和工作机理。通过2根方钢管混凝土短柱和6根组合方钢管混凝土短柱的轴心受压试验,研究方钢管混凝土柱和组合方钢管混凝土柱力学性能的差异以及截面形式、含钢率、混凝土强度和套箍系数等因素对组合柱受力性能的影响规律;对加荷过程中方钢管和混凝土中各种内力的变化进行分析计算,揭示方钢管混凝土柱轴心受压时两种材料的工作机理。利用有限元分析软件ABAQUS对方钢管混凝土轴压短柱和组合方钢管混凝土轴压短柱的荷载-变形全过程进行计算。计算结果与试验结果吻合较好,表明本文建立的有限元模型可以用于方钢管混凝土柱和组合方钢管混凝土柱的轴心受压计算。用有限元法计算了27根普通方钢管混凝土短柱和27根组合方钢管混凝土短柱的轴心受压承载力,通过对计算结果进行回归分析,得出了方钢管混凝土柱和组合方钢管混凝土柱轴心受压承载力的计算公式。公式计算结果与试验结果吻合较好,且公式形式简单、概念清晰,可为有关工程实践和规程制订提供参考。更多还原

【Abstract】 The CFSST(concrete-filled square steel tube) has the advantages of high bearing capacity, good ductility, rapid construction speed, regular shape, simple connections between columns and beams. Due to it’s good behaviour, it is used more and more widely in engineering practice. But the confinement effect of square steel tube is not obvious, the bearing capacity of column improves little. In order to overcome the disadvantages of CFSST, a new type composite section CFSST column is designed in this paper. The behaviour and mechanism of this composite section CFSST column under axial load were investigated, including theoretical and experimental studies.By the axial compress experimentation of two CFSST specimens and six composite section CFSST column, the differences of mechanical properties between CFSST and composite section CFSST and the influence law of section type, steel ratio, strength of concrete and confinement index on the behavior of composite section columns are studied. The internal force of square steel tube and concrete were analyzed and the mechanism of two materials of CFSST were studied under axial load.Load-deformation curve of CFSST column and composite section CFSST column under axial load was analyzed by ABAQUS, which is a common analysis software of finite element method(FEM). The results of calculation coincide well to experimental data. It shows that the finite elements model established in this paper could be used to calculate the bearing capacity of CFSST column and composite section CFSST column under axial load. Bearing capacity of twenty-seven CFSST and twenty-seven composite section CFSST short column under axial load were calculated by finite element method. The formulas of ultimate axial compressive strength of the column of CFSST and composite section CFSST are obtained form the analysis results. Theoretical results are verified by tests results, and the formulas have clear mechanics concept, simple form, which can supply reliable references to practical engineering and specifications.更多还原