自复位预应力预制框架静力弹塑性分析

Pushover analysis of self-centering pre-stressed precast frame

采用基于能量概念的简化公式确定自复位预应力预制框架(PTED)结构的目标位移。建立PTED结构的有限元分析模型,对PTED结构进行静力弹塑性分析,验证大震下结构的层间位移角,梁、柱连接处及柱底转动能力能否满足规范要求。探讨PTED结构中梁的伸长效应及底层柱纵筋取值对结构受力性能的影响。研究结果表明:结构的最大层间位移角,梁、柱连接处的转角及柱底塑性铰满足大震下的变形要求,结构为梁铰耗能机制、抗震性能良好。梁伸长对梁、柱的局部受力性能影响较大,但对框架结构整体性能影响不大。在结构设计中应合理估计底层柱纵筋面积,以期得到较优的抗震性能。

The simplified formula based on energy concept was utilized to determine the target displacement of self-centering pre-stressed precast frame( PTED). The finite element analysis model of PTED structure was established and the Pushover analysis was carried out to verify if the storey drift of the structure,the rotation capacity of beam-column joint and bottom part of column can meet the specification requirements under the rare earthquake. The elongation of the beam and longitudinal reinforcement of bottom columns on the seismic performance of the structure were studied. The study results show that the storey drift of structure,the rotation angle of beam-column joint and plastic hinge of bottom part of column can meet the specification deformation requirements under the rare earthquake. The structure has well seismic performance with beam hinge energy dissipation mechanism. The elongation of the beam has little effect on the overall seismic performance of the structure except local mechanical performances of some beams and columns. The longitudinal reinforcement areas of bottom columns should be estimated reasonably to get the optimal seismic performance of the structure.