以二维钢框架为例,首先根据构件移除指标公式确定出结构中的关键构件,然后采用结构连续倒塌分析的改变路径法,通过时间历史分析函数将分析得到的关键构件从结构中移除.以需求能力比和转角作为失效准则,对剩余结构进行验算,分析构件移除对结构力学行为的影响.随后对剩余结构进行火灾次生灾害分析,研究火灾对结构产生的破坏作用.在给出构件失效后结构最大动力响应的同时,对剩余结构在火灾作用下的完整失效过程进行深入地研究,给出了一种受损伤结构的抗火分析方法.通过完整结构和受损伤结构受火行为的比较,得到不同结构火灾作用下的倒塌机理. Taking the two-dimensional steel frame as an example, the key components of the structure are first determined according to the formula of component removal index, then the change path method of continuous collapse analysis of structure is adopted, and the key components analyzed are removed from the structure by time history analysis function .According to requirement ratio and rotation angle as failure criteria, the remaining structures were checked and the influence of component removal on structural mechanics behavior was analyzed.After that, the remaining structures were analyzed for secondary disasters, and the destructive effect of fire on structures was analyzed. At the same time, the complete failure process of the remaining structure under fire is studied in depth, and a fire resistance analysis method of the damaged structure is given.After the complete structure and damaged structure are exposed to fire Behavior comparison, get the collapse mechanism under the different structure fire.