高温后型钢混凝土框架结构抗震性能及其有限元分析

考虑受火时间、柱轴压比的影响,进行了考虑火灾升降温作用影响的高温后型钢混凝土框架结构抗震性能试验,升降温过程中和高温后阶段均保持柱顶竖向荷载的恒定。通过试验对高温后型钢混凝土框架结构在反复荷载作用下的破坏形态及滞回性能进行了研究。在此基础上,考虑升温阶段、降温阶段以及火灾后三阶段材料本构关系的转化以及型钢与混凝土之间、钢筋与混凝土之间界面的黏结滑移特性,建立了型钢混凝土框架结构温度场以及火灾后抗震性能的有限元分析模型,所得温度场以及试件的破坏形态、滞回曲线的分析结果与试验结果基本吻合,验证了所提出模型的合理性。

A finite element analysis model for post-fire seismic performance of steel reinforced concrete frame structures

Taking into consideration the parameters such as heating time and axial compression ratio of the frame column, an experiment was carried out to study the post-fire seismic performance of steel reinforced concrete (SRC) frame structures subjected to fire including a cooling phase, and the vertical load kept constant during and after the fire. The failure mode and the hysteretic properties of the frame specimens were studied based on the test. On the basis of the experimental results, a finite element analysis (FEA) model for the temperature field and the post-fire seismic performance of the steel reinforced concrete frame structures was proposed. In the FEA model, the change of material constitutive behavior in the following three stages was considered: temperature increase, temperature decrease and post-fire stage; the bond-slip properties of the interfaces between steel and concrete and between rebar and concrete were also considered. It shows that the calculated temperature field agrees well with the test results, and that the deformation, failure mode and hysteretic curve also agree well with the test results. It can be concluded that the proposed FEA model is reasonable.