不同轴压比下预制装配式部分钢骨梁柱节点动力性能研究

Study on dynamic behavior of precast and partial steel beam-column joint under different axial compression ratios

考虑约束效应、强度退化及应变率效应,运用ABAQUS有限元分析软件,建立了预制装配式部分钢骨钢筋混凝土(PPSRC)梁柱节点力学性能有限元分析模型,通过试验结果验证该模型的有效性,采用验证后的有限元模型,研究了不同轴压比下PPSRC梁柱节点的动态力学性能。研究表明,提出的有限元分析模型可较好地预测PPSRC梁柱节点的力学性能。受应变率效应的影响,动态荷载作用下轴压比对PPSRC梁柱节点的承载力影响不大,PPSRC梁柱边节点的承载力随轴压比的提高无明显变化,轴压比提高后,PPSRC梁柱中节点的屈服承载力和极限承载力略有增大,但较大位移水平下,轴压比高的PPSRC梁柱中节点,其承载力退化更加明显;相同位移水平下,正向加载时的刚度始终大于反向加载时的刚度,轴压比提高后,PPSRC梁柱节点的刚度增大,但较大位移水平下,轴压比高的PPSRC梁柱节点,其刚度退化更加明显;轴压比对PPSRC梁柱节点的延性性能无明显影响;轴压比提高后,PPSRC梁柱节点的耗能能力提高。

In con sideration of the constraint effect,strength deterioration and strain rate effect,a finite element model was developed through the finite element analysis software ABAQUS to predict the mechanical properties of precast and partial steel reinforced concrete(PPSRC)beam-column joint.The validity of the proposed model was verified through experimental results.Based on the verified finite element model,the dynamic mechanical properties of PPSRC beam-column joints under different axial compression ratios were studied.Research shows that the proposed finite element analysis model can well predict the mechanical properties of PPSRC beam-column joint.Owing to the strain rate effect,the change of axial compression ratio has little effect on the carrying capacity of PPSRC beam column joint under dynamic loading.With the increase of axial compression ratio,there is no obvious change for the carrying capacity of PPSRC exterior beam-column joint.The yield carrying capacity and ultimate carrying capacity of PPSRC interior beam-column joint increase slightly as the axial compression ratio increases.However,the carrying capacity degradation of PPSRC interior beam-column joint with higher axial compression ratio is more obvious,at larger displacement level.Under the same displacement level,the stiffness of forward loading is always greater than that of reverse loading.An increase in the axial compression ratio leads to an increase in the stiffness of PPSRC beam-column joint.However,at larger displacement level,the stiffness degradation of PPSRC beam-column joint with higher axial compression ratio is more obvious.The change of axial compression ratio has no significant effect on the ductility performance of PPSRC beam-column joint.With the increase of axial compression ratio,the energy dissipation capacity of PPSRC beam-column joint increases.