火灾后PPEFF节点抗震性能变化的研究分析

Research and analysis on seismic performance change of PPEFF joints after fire

对2个足尺预压装配式混凝土梁柱节点在常温环境下进行了低周反复试验。同时,借助ABAQUS建立对应的火灾后的有限元分析模型,通过国际标准化委员会标准ISO-834升温曲线对构件进行升温(升温时长为60 min),对受火灾作用后的节点进行了低周反复荷载下的模拟分析。通过模拟分析,证明了节点在经历火灾后仍具备一定的支持能力、耐火完整性和隔热性,但对比常温环境下的试验研究表明,火灾后PPEFF节点的屈服强度出现了明显的降低,延性下降,耗能能力退化严重。

Two full-scale precast concrete beam column joints tested under low cyclic loading at room temperature.At the same time,the coresponding finite element analysis model after fire is established by ABAQUS,and the component is heated up by ISO-834 temperature rising curve of the International Committee for Standardization(the heating time is 60 minutes).The joints affected by fire are simulated and analyzed under low-cycle repeated load.Through simulation analysis,it is proved that the PPEFF joint stil has certain support ability,fire-resistance integrity and heat insulation after experiencing temperature rise.However,the test results show that under normal temperature environment,the yield strength,ductility and energy consumption capacity of the PPEFF joint significantly decrease after fire.