新型钢管混凝土叠合柱轴压力学性能研究

发布时间：2018-02-16 08:14

本文关键词： 钢管混凝土叠合柱轴压有限元中空强度稳定　出处：《福州大学》2013年硕士论文　论文类型：学位论文

【摘要】：钢管混凝土承载力高、延性好,但钢管暴露在空气中,在火灾作用下容易丧失承载力。而钢筋混凝土的耐火性能要优于钢管混凝土构件。因此由内部钢管混凝土柱和外包钢筋混凝土组合而成的钢管混凝土叠合柱有望同时具有两者的优点。在此背景下,钢管混凝土叠合柱受到越来越多研究者们的关注,且被逐渐应用于建筑工程和桥梁工程中。但目前对其轴压力学性能的研究还不够深入,特别是对含多管的新型中空钢管混凝土叠合柱的研究仍处于起步阶段。本文采用试验研究和理论分析相结合的方法,深入研究钢管混凝土叠合柱的轴压力学性能。主要进行了以下几个方面的工作：(1)首先较为系统地综述了国内外相关的研究现状,以论证本课题研究的必要性。(2)进行了12个钢管混凝土叠合柱的轴压试验,其中包括4个方形实心叠合柱、4个圆形实心叠合柱以及4个方形中空叠合柱。试验的参数包括管内混凝土强度和截面类型,主要分析不同参数对叠合柱破坏形态、极限承载力和延性的影响规律。研究结果表明圆形钢管混凝土叠合柱比方形钢管混凝土叠合柱的承载力高；实心截面构件的延性明显优于中空截面的构件。(3)建立有限元模型,比较了几种混凝土模型,最终确定较为合适的混凝土本构模型。该模型的合理性得到了38个实验数据的充分验证。(4)基于有限元模型进行了深入的机理分析。主要分析叠合柱的破坏模态、荷载分配比例、应力、应变和接触力的分布规律。同时还进行了大量的参数分析,主要分析管外混凝土强度、管内混凝土强度、钢管屈服强度、含钢管混凝土率、箍筋间距和长细比等参数对构件承载力的影响规律。研究表明提高混凝土强度、钢管混凝土屈服强度和含钢管混凝土率可有效的提高叠合柱的承载力；外包混凝土的峰值应变约等于0.0022。(5)最终基于机理分析和参数分析的结论,建议了钢管混凝土叠合柱的强度和稳定承载力的计算公式,简化计算结果与试验结果吻合较好,可为工程实践提供参考。
[Abstract]:Concrete filled steel tube has high bearing capacity and good ductility, but the steel tube is exposed to air. It is easy to lose the bearing capacity under the action of fire, and the fire resistance of reinforced concrete is better than that of concrete filled steel tube. Therefore, the composite column of steel tube concrete filled with outer reinforced concrete is expected to be composed of inner concrete-filled steel tube column and external reinforced concrete column. Have the advantages of both. In this context, Composite columns of concrete-filled steel tubular (CFST) have attracted more and more attention and have been gradually applied in building engineering and bridge engineering. However, the research on axial compressive mechanical properties of CFST composite columns is not deep enough. In particular, the study of new hollow concrete-filled steel tubular composite columns with multiple pipes is still in its infancy. In this paper, the method of combining experimental research with theoretical analysis is adopted. The axial compressive mechanical properties of concrete-filled steel tubular composite columns are studied in depth. The main work is as follows: firstly, the relative research status at home and abroad is systematically summarized. In order to prove the necessity of this research, the axial compression tests of 12 concrete-filled steel tubular composite columns are carried out. It includes four square solid superimposed columns, four circular solid superimposed columns and four square hollow composite columns. The results show that the bearing capacity of circular concrete-filled steel tubular composite columns is higher than that of square concrete-filled steel tube composite columns, and the ductility of solid section members is obviously better than that of hollow section members. Several concrete models are compared. Finally, a more suitable concrete constitutive model is determined. The rationality of the model is fully verified by 38 experimental data. The mechanism is analyzed based on the finite element model. The failure mode and load distribution ratio of the superimposed columns are analyzed. The distribution law of stress, strain and contact force. At the same time, a large number of parameter analysis have been carried out, mainly analyzing the strength of concrete outside the pipe, the strength of concrete inside the pipe, the yield strength of steel tube, the ratio of concrete filled with steel tube, The effect of stirrups spacing and aspect ratio on the bearing capacity of composite columns is studied. The results show that the bearing capacity of composite columns can be improved effectively by increasing concrete strength, yield strength and concrete filled steel tube ratio. Finally, based on the conclusion of mechanism analysis and parameter analysis, the calculation formulas of strength and stability bearing capacity of concrete filled steel tubular columns are suggested. The simplified calculation results are in good agreement with the experimental results. It can provide reference for engineering practice.
【学位授予单位】：福州大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU398.9

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