基于给定的核心混凝土和钢材的三轴本构模型,设定构件内、外两层钢管使用相同的钢材,并考虑核心混凝土和钢管变形协调,应用连续介质力学理论,对中空夹层钢管混凝土短柱进行了弹塑性全过程理论分析,建立了中空夹层钢管混凝土短柱组合弹性模量理论计算公式和应力-应变关系全曲线的理论计算模型。该计算模型形式简单,参数少易确定,便于程序化实现,并与文献资料的试验结果进行了比较,结果表明,该模型能较好地反映试验规律以及组合构件材料物理性能的优点,为中空夹层钢管混凝土组合结构进一步研究奠定了基础。
Based on the triaxial constitutive relations of the core concrete and the steel, an elasto-plastic analysis of concrete filled double skin steel tube columns is presented by the method of continuous medium mechanics. Taking into account the assumption that the inner and the outer steel tubes are made of the same steel, and assuming that the steel tubes and the concrete core deform compatibly, the theoretical formula for elastic modulus and the theoretical calculation model for stress-strain curves of the composite material of concrete filled double skin steel tube columns are proposed. The proposed model has simple form with few parameters and can be conveniently used for number analysis. Compared with the results obtained from this work and the experimental results, good agreement can be observed. It is shown that the proposed model can accurately simulate the physical properties of composite structure and can be applied to further analysis of the concrete filled double skin steel tube columns.