T形钢管混凝土柱荷载-位移骨架曲线模型

Research on load-displacement skeleton curve model of T-shaped concrete-filled steel tubular column

文章采用有限元分析软件ABAQUS对T形钢管混凝土柱的抗震性能进行了数值分析,基于低周反复荷载作用下有限元计算的荷载-位移滞回曲线,得出了T形钢管混凝土柱的荷载-位移骨架曲线,通过对有限元计算结果进行回归分析,提出了T形钢管混凝土柱荷载-位移骨架曲线模型,充分考虑了轴压比、套箍系数、长细比对骨架曲线的影响,推导了模型参数(弹性阶段刚度、屈服荷载、强化阶段刚度)计算表达式,并引入修正系数η对弹性阶段刚度进行修正,最后将模型计算结果与有限元计算结果进行了对比。分析结果表明:弹性阶段刚度有限元计算值偏大,经修正误差控制在一定范围内;轴压比、套箍系数、长细比对屈服荷载和强化阶段刚度影响较大;模型计算结果与有限元计算结果吻合较好,该模型具有一定的计算精度和应用价值,可为后续研究提供参考。

By using finite element analysis software ABAQUS, the non-linear analysis of seismic performance of T-shaped concrete-filled steel tubular columns is made. Based on the load-displacement hysteresis curves ob- tained by the finite element calculation under the low cyclic reversed loading, the load-displacement skeleton curves of T-shaped concrete-filled steel tubular columns are obtained. By the regression analysis based on the finite element calculation results, the load-displacement skeleton curve model considering the influence of axial compression ratio, confinement coefficient and slenderness ratio on skeleton curves is put forward, and the calculation expressions of model parameters including elastic stiffness, yield load and stiffness in the strength- ening stage are derived. The correction factor r/is introduced to reuse elastic stiffness, then the model calcula- tion results and the finite element calculation results are compared. The results are as follows, the elastic stiffness finite element calculation value is larger, the correction error is controlled in a certain range~ the axial compression ratio, confinement coefficient and slenderness ratio have greater influence on yield load and stiff- ness in the strengthening stage~ the model calculation results agree well with the finite element calculation re- sults, the model has certain calculation precision and application value, and provides a good reference for the seismic design of T-shaped concrete-filled steel tubular column.