【摘要】 为研究局部火灾引起多高层钢结构倒塌的破坏机理以及多高层钢结构在火灾下的抗倒塌性能,基于结构初始倒塌破坏机制,建立了单柱受火的火灾引起多高层钢结构倒塌分析的单自由度简化分析模型,模型将受火柱上部结构简化为三折线弹塑性弹簧模型,将受火柱简化为集中塑性铰模型,并推导了基于能量的结构反应计算公式,建立了能量的计算方法。最后通过整体结构的数值对比分析,验证了此方法用于火灾引起钢结构连续倒塌分析与计算的合理性与可行性。更多还原

【Abstract】 To study the collapse mechanism and collapse resistance of steel structures subjected to local fire, a simplified collapse analysis model with single degree of freedom is established based on the initial collapse mechanism of steel structures under fire. In this model, the superstructure is modeled as a constraint spring with tri-linear elastic-plastic properties, and the heated column is simplified as a lumped plastic hinge model. Then the energy-based formula to calculate the structure response is deduced. Finally the rationality and feasibility of the proposed model and method are validated through a comparison with the numerical analysis results of the whole structure subjected to local fire.更多还原