火灾作用后型钢混凝土柱滞回性能研究

摘要

After exposure to fire,the seismic performance of SRC columns would be deteriorated be-cause of the loss of mechanical properties of concrete under high temperature.To reveal the impact of fire exposure on the seismic performance of SRC columns,the FEM software ABAQUS was used to calculate the hysteretic lateral load versus lateral displacement relations based on full process analysis.Influences of the changing axial compression ratio and fire duration time on the lateral load versus lateral displacement skele-ton curves were discussed.Results showed that the hysteretic curves of the steel reinforced concrete columns are in plump shapes,and have no significant pinch phenomenon after exposure to fire;the ultimate load-car-rying capacity will decrease with the increase of fire duration time and axial compression ratio;fire duration time has a greater impact on the elastic stiffness than axial compression ratio.%型钢混凝土柱在遭受火灾作用后，由于混凝土的力学性能受到损伤，导致柱的抗震性能劣化。为揭示火灾高温损伤对型钢混凝土柱抗震性能的影响，文章运用ABAQUS软件，基于全过程分析方法，建立了火灾作用后型钢混凝土柱滞回性能分析模型，对火灾后SRC柱荷载-位移滞回关系进行计算，分析了轴压比、受火时间对荷载-位移关系骨架线的影响规律。研究结果表明：火灾作用后型钢混凝土柱滞回关系曲线形状饱满，无明显捏缩现象；随着升温时间和轴压比的增大，高温后构件的极限承载力变小；相对于轴压比，升温时间对构件的弹性刚度有着较大的影响。