钢管轻集料混凝土柱滞回性能影响因素研究

Study on Influencing Factors of Hysteretic Behavior of Lightweight Aggregate Concrete Filled Steel Tubular Columns

对钢管轻集料混凝土构件在水平往复荷载作用下的滞回性能进行了试验研究和有限元计算。分别以材料强度、轴压比和含钢率的变化为参数设计构件。混凝土本构模型采用修正后的塑性损伤模型,计算得到的各构件滞回曲线与试验结果对比,验证了模型的准确性。研究结果表明,钢管轻集料混凝土柱的破坏形态为钢管底部位置的局部鼓曲破坏,核心混凝土以受压损伤破坏为主;构件滞回曲线饱满,骨架曲线完整,表现出较好的滞回性能。核心轻集料混凝土强度、轴压比、径厚比和钢管强度分别对骨架曲线产生了一定的影响。各构件等效粘滞阻尼系数基本在0. 35左右,表现出了较好的耗能性能。

The hysteretic behavior of lightweight aggregate concrete filled steel tube components under horizontal cyclic loading was studied by experiment and calculated by using finite element software.The components were designed according to the strength of materials,axial compression ratio and steel ratio.A modified plastic damage model was adopted in the concrete constitutive model.The accuracy of the model was verified by comparing the hysteretic curves of the calculated components with the tests.The results show that the failure of the lightweight aggregate concrete column was the local buckling of the steel tube at the bottom,and the core concrete was mainly damaged by compression.The hysteretic curves of the components were full and the skeleton curves were complete,showing good hysteretic behavior.The strength of core lightweight aggregate concrete,axial compression ratio,diameter thickness ratio and strength of steel pipe had a certain effect on the skeleton curve.The equivalent viscous damping coefficient of each component was basically around 0.35,showing a good energy dissipation performance.