【作者】 杜闯；

【导师】 王铁成；

【作者基本信息】 天津大学 ， 结构工程， 2011， 博士

【摘要】 钢管混凝土结构是一种新型的结构体系，由于它具有较好的抗震性能，目前越来越多的应用于高层、超高层、大跨度等结构中。但对于钢管混凝土这种新的结构体系，无论是从试验上还是理论上来说，研究的都比较少。相对而言，传统的钢筋混凝土经过国内外许多学者多年的研究工作，其发展的理论已经比较成熟。本文从这一想法出发，以钢筋混凝土为参照，将钢管混凝土与之进行比较来研究钢管混凝土的力学性能。本文所做的研究工作主要有以下几个部分：对ANSYS非线性有限元模拟中的一些问题，主要是结合钢管混凝土和钢筋混凝土非线性计算中涉及到的关键问题，包括：材料本构模型、单元、ANSYS有限元非线性计算原理、ANSYS建模以及实际有限元应用中应该注意的问题做了总结。比较了同等条件下的钢管混凝土柱和钢筋混凝土柱轴压受力性能。对国内外轴压下的钢管混凝土柱和钢筋混凝土柱的规范设计公式进行了对比，分析了不同规范计算公式的特点。类比螺旋配箍钢筋混凝土柱受压计算公式的基础上，根据方钢管混凝土柱的约束特点，将核心混凝土分为强约束区和弱约束区，提出了一种新的计算方钢管混凝土柱轴压承载力的公式，并和试验结果进行了对比。比较相同条件下钢管混凝土柱和钢筋混凝土柱偏压受力性能，包括破坏形态、受力机理、变形以及承载力。采用参数化方法分析了偏心率和长细比对钢管混凝土柱和钢筋混凝土柱力学性能的影响规律。比较了钢管混凝土柱和钢筋混凝土压弯时的设计公式，分析了钢管混凝土设计公式和钢筋混凝土设计公式的不同特点。类比钢筋混凝土柱压弯计算公式，采用大小偏心的概念建立了钢管混凝土柱压弯承载力计算公式。建立了钢管混凝土柱在低周往复荷载下的有限元模型，并通过试验验证了有限元模型的可靠性。在此基础上，对同等条件下的钢管混凝土柱和钢筋混凝土柱进行了低周往复荷载有限元模拟，对比分析了包括破坏形态、滞回曲线、骨架曲线、承载力、延性、耗能能力、强度退化和刚度退化等力学性能。选取天津波，对钢管混凝土框架和钢筋混凝土框架进行了动力时程分析，比较了动力特性、位移和加速度等动力响应。分析的结果表明，钢管混凝土框架柱在多遇地震下，其优势并不明显，但在罕遇地震时，其抗震性能明显优于钢筋混凝土框架。更多还原

【Abstract】 As a new structural system, concrete-filled steel tubular(CFST) structure is moreand more used in high-rise, super high-rise, large span structures because it has betterseismic performance. But for the new structural system of CFST, researches are quitea few both in the theory and in the experiment. Relatively speaking, the traditionalreinforced concrete (RC)structural system has been studied by many scholars at homeand abroad for many years, its development of the theory is more mature. Startingfrom this idea, this paper takes reinforced concrete as the reference to carry on thecomparative study on the mechanical properties of the concrete filled steel tubularstructure. This research works mainly have the following several parts.Introducing some key questions which are involved in non-linear calculation ofconcrete-filled steel tubular and reinforced concrete when using ANSYS finiteelement software,it include the material constitutive model,element,ANSYS nonlinearbasic principle, modelling and some tips in practical application.The mechanical properties of CFST cloumn and RC column subjected to axialforce is compared under the same conditions. The design formula of CFST cloumnand RC column is compared under axial load from the different country codes andtheir formula characteristic is analyzed. Based on RC columns with spiral stirrupcalculation principle, a new capacity formula of square CFST column is proposedthrough dividing the areas of core concrete of CFST column into weak and strongrestraint area according to its restraint characteristic and compared the calculatedresults with the experimental results to verify the proposed formula.The mechanical properties of CFST cloumn and RC column,including failuremodes, mechanical mechanism, deformation and bearing capacity are compared underthe same eccentric load.The eccentricity and the slenderness ratio of CFST cloumnand RC column are analyzed to obtain their influence on the mechanical properties bythe parameter method.The design formula of CFST cloumn and RC column undereccentric load is compared and their design formula characteristic is analyzed.Base onRC column formula under eccentric load,a new formula of CFST column isproposed adopting the concept of large eccentricity and small eccentricity.The finite element model of CFST column under cyclic loading is establishedand the model reliability is verified through the experiment. On this basis, CFSTcolumn and RC column subjected to cyclic load is simulated to compare their mechanical properties,including the failure modes, hysteresis curve, skeleton curve,bearing capacity, ductility, dissipation energy capacity, strength degradation andstiffness degradation and so on under the same conditions.Selecting Tianjin wave, seismic response analysis is done by using time historyanalysis method in CFST frame and RC frame, compared with their dynamicresponses including the dynamic characteristics, the displacement and the acceleration.The analysis results indicate that CFST frame is not obvious advantage over RC frameunder frequently occurred earthquake,but seismic behavior of CFST frame isobviously superior to the RC frame under rare earthquake.更多还原