改进组合式T形钢管内核心混凝土应力-应变关系

Stress-strain relationship for core concrete of improved composite T-shaped steel tube

文章基于改进组合式T形钢管混凝土柱轴压试验结果,详细分析了在轴压状态下钢管对核心混凝土的约束特点,通过截面合理划分和假定,并借鉴已有的箍筋约束混凝土应力-应变关系,提出了改进组合式T形钢管内核心混凝土应力-应变关系;在分析主要影响参数的基础上,给出了应力-应变关系参数计算表达式;采用有限元软件ABAQUS对改进组合式T形钢管混凝土柱轴压荷载-应变关系曲线进行了数值计算,并将有限元计算结果与试验结果进行对比。研究结果表明,有限元计算结果与试验结果吻合较好,验证了所提核心混凝土应力-应变关系的合理性。

Based on the axial compressive experimental results of improved composite T-shaped con- crete-filled steel tubular columns, the constraint characteristic of steel tube to core concrete under axi- al compressive load was analyzed. According to the existing stress-strain relationship for stirrup con- fined concrete, the stress-strain relationship for the core concrete of improved composite T-shaped steel tube was proposed by reasonable section division and assumption. Based on the analysis of the key influencing parameters, the parameter calculation expressions of stress-strain relationship were given. Then the load-strain curves of the improved composite T-shaped concrete-filled steel tubular columns were analyzed with the proposed stress-strain relationship by using finite element software ABAQUS, where the results calculated by ABAQUS were compared with the experimental results. It is shown that the results calculated by ABAQUS agree well with the experimental results, thus verif- ying the rationality of the proposed stress-strain relationship.