Abstract To study the dynamic behavior of steel frames after a sudden column failure scenario, an experimental study was performed on a steel frame with three stories by employing an air cylinder to simulate the sudden failure of a column. The experimental results indicate that the remaining structure underwent a large plastic deformation and developed a distinct catenary action in the beams, and this action was more substantial for the first-floor beams compared to the other floor beams. A finite element model (FEM) was established and validated based on the experimental results. The influence of the material strain rate in the structural progressive collapse was analyzed. Comparing the results obtained in the numerical simulation and those obtained using the Department of Defense (DoD) standard equation, indicated that the dynamic increase factor is in the range of 1–2 when conducting static inelastic analysis on steel frames. The equation of the dynamic increase factor in the DoD standard can accurately reflect the dynamic effect of steel frames to a certain extent. However, the results provided by this equation monotonously decrease with the increase in the structural plastic deformation and do not correctly predict the rebound of the dynamic increase factor when the structural material enters the strengthening stage.

中文翻译：

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连续倒塌过程中钢框架动力行为的试验研究

摘要 为研究柱突然破坏后钢框架的动力行为，对三层钢框架进行了试验研究，采用气缸模拟柱的突然破坏。实验结果表明，其余结构发生了较大的塑性变形，并在梁中产生了明显的悬链线作用，与其他地板梁相比，一层梁的这种作用更为显着。基于实验结果建立并验证了有限元模型（FEM）。分析了材料应变率对结构连续倒塌的影响。比较在数值模拟中获得的结果和使用国防部 (DoD) 标准方程获得的结果，表明在对钢框架进行静态非弹性分析时，动力增加系数在 1-2 的范围内。DoD标准中的动态增加系数方程可以在一定程度上准确反映钢框架的动态效果。然而，该方程提供的结果随着结构塑性变形的增加而单调递减，并不能正确预测结构材料进入强化阶段时动力增加因子的回弹。