水平冲击荷载作用下钢管混凝土柱动力响应试验与数值模拟

为研究钢管混凝土柱在侧向冲击荷载作用下的动力性能，进行了2根圆形钢管混凝土柱的水平冲击试验，实测了冲击过程中冲击力、冲击点位移时程曲线及冲击力-位移曲线等冲击响应。建立了ABAQUS非线性有限元模型，对破坏模态及冲击力、冲击点位移时程曲线等动态响应进行模拟，模拟结果与试验结果吻合良好，进而用有限元模拟结果揭示了钢管混凝土柱在冲击荷载下的破坏机理，即整体失效过程分为冲击区局部响应、柱顶支座响应、稳定响应和卸载响应4个阶段。结果表明:在冲击荷载作用下，钢管混凝土柱发生弯剪型破坏；所得结论为深入认识钢管混凝土柱的抗冲击行为和破坏形态提供了试验与理论基础，可为今后研究制定合理的抗冲击设计方法提供依据。

Dynamic Response Experiment and Numerical Simulation of CFST Columns Under Lateral Impact Load

In order to study the dynamic behaviors of concrete-filled steel tube (CFST) column under lateral impact load，lateral impact tests for two circular CFST columns were conducted, and impact force, impact point deflection-time curves as well as force-deflection curves were measured. Impact process of CFST column under impact load was simulated by using ABAQUS nonlinear model, the failure mode and time-history curves of impact force, impact point deflection were obtained, and the simulation results agreed well with the experimental ones. The modeling results revealed the failure mechanism of CFST columns under impact load. The global failure process were divided into four stages, local response phase in the impact zone, support response phase on the column top, steady response phase and unloading response phase. The results show that CFST columns appear bending-shear failure under impact load. The research can provide experimental and theoretical basis to deeply understand the impact resistance and failure mode of CTST column, and it can provide evidence for reasonable anti-impact design method.