Beam-column sub-assemblage is an important component in frame system. Many studies revealed that over-large or too-low axial compression ratio result poor seismic performance for beam-column sub-assemblages. Six full-scale low, medium and high shear-compression ratio specimens reinforced with high performance reinforcement (HRB500E) had been designed to study the seismic performance that are less researched under low axial compression ratio. Specimens were tested under quasi-static load with low axial compression ratio and medium axial compression ratio. The seismic performance including failure mode, hysteretic loops, skeleton curves, ductility ratio, energy-dissipation ratio and stiffness degradation ratio of these specimens were obtained and compared. The results indicate that under low and medium compression ratios,low axial compression ratio is bad for core area protection. Reducing the compression ratio results in different failure modes, while the failure modes of high compression ratio specimens show no different. The low axial compression specimens have a reduced ductility performance compared to medium axial compression specimens. And the reducing rate decreased as the shear-compression ratio increased. The low shear-compression ratio specimen SP1 has bad seismic performance in energy-dissipation capacity under low axial compression ratio due to significant bar-slip in beam,whilst the medium and high shear-compression ratio specimens SP2,SP3 have better energy-dissipation performance than medium axial compression specimens SP5,SP6.%轴压比会对梁柱组合体节点的抗震性能带来影响.本文设计了6个配置高性能钢筋(HRB500E)的足尺低、中、高剪压比梁柱组合体试件,分别在低、中轴压比情况下进行拟静力加载试验,得到各个试件的破坏模式、滞回曲线、骨架曲线、延性系数、耗能系数以及刚度退化率并进行对比.试验结果表明:中低剪压比情况下,低轴压比不利于核心区的保护,降低轴压比使得试件的破坏模式发生改变,高剪压比下的试件破坏模式一致;低轴压比时,试件的延性性能比中轴压比试件有所降低,但是随着剪压比的提升,降低的幅度越来越小;低轴压比下,低剪压比试件SP1由于梁纵筋的粘结滑移较为严重,导致能量耗散抗震性能表现较差,但中高剪压比试件SP2,SP3能量耗散性能好于中轴压比试件SP5,SP6.
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