不同轴压比下浆锚连接装配式异形柱框架结构的抗震性能试验研究

Experimental study on seismic performance of precast concrete frame structure with specially shaped column of grouting connection at different axial compression ratios

为研究不同轴压比下混凝土异形柱框架结构的抗震性能,采用“浆锚连接+节点后浇”装配方案,设计并制作轴压比分别为0.14和0.28的足尺试件PCFS1和PCFS2,并对其进行低周循环往复加载试验。研究结果表明:“浆锚连接+节点后浇”连接方案安全可靠,试件PCFS1和PCFS2初裂分别出现在一层柱底部灌浆口、梁两端竖向拼接处,结构失效均以梁铰破坏为主;试件滞回曲线均呈反“S”形,轴压比增大后滑移现象减轻,捏拢现象显现,极限变形与耗能能力下降,延性降低,但耗能与承载稳定性能均较好,满足延性要求;2个试件各层及整体结构的极限弹塑性层间位移角均满足“大震不倒”抗震设防限值要求。在浆锚连接装配式混凝土异形柱框架结构的实际应用中,建议采取有效措施以推迟首条裂缝出现的时间,并在弹性分析时考虑结构的整体空间效应。

In order to study the seismic performance of the precast concrete specially shaped column frame structure at different axial compression ratios,full-size specimens PCFS1 and PCFS2 with axial compression ratios of 0.14 and 0.28 respectively were designed and prepared by using the scheme of"grouting connection and the post-cast beam-column joint"to carry out low reversed cyclic loading test.The results show that the scheme of"grouting connection and the post-cast beam-column joint"is safe and reliable.The specimens PCFS1 and PCFS2 are initially cracked at the grouting opening holes at the column foot of the first floor and vertical splicing at both ends of the beam,respectively.The failure mode of the structure is mainly beam hinge failure.The hysteretic curves show an inverse"S"shape.With the increase of axial compression ratio,the slip phenomenon is weakened,the squeezing phenomenon appears,and the ultimate deformation capacity,energy dissipation capacity and the ductility all decrease.However,they all show good bearing stability capacity and energy dissipation capacity,which meet the requirements of the ductile frame.The ultimate elastic-plastic interlayer displacement angles for each floor and the whole structures of two specimens all meet seismic fortification limit requirements of"no collapse during strong earthquake".In practical application of the precast concrete frame structure with specially shaped column of grouting connection,it is suggested to take effective measures to delay the appearance of first crack,and the overall spatial effect of the structure also need to be considered in elastic analysis.