活性粉末混凝土(RPC)梁柱节点抗震性能非线性有限元分析

Nonlinear Finite Element Analysis for Seismic Performance of Reactive Powder Concrete(RPC) Beam-column Joints

为了研究活性粉末混凝土(RPC)梁柱节点的抗震性能,本文运用有限元软件ABAQUS,对22个RPC梁柱节点进行分析,得到各节点的滞回曲线和骨架曲线,研究柱端轴压比、节点核芯区箍筋配筋率和梁、柱纵筋配筋率对RPC梁柱节点的滞回特性、延性、承载力等抗震性能的影响规律.研究发现,RPC梁柱节点与高强混凝土梁柱节点受力变化规律基本一致.随着轴压比的增加,RPC梁柱节点延性显著下降,当轴压比低于0.6时,构件极限承载力随轴压比增加而增加,当轴压比高于0.6时,构件极限承载力开始呈现下降趋势;随着节点核芯箍筋配筋率的增加,延缓了构件强度与刚度的退化,并使构件的延性、极限承载力有所提升,当节点核芯配箍率低于1.01%时,构件的承载能力和塑形变形能力较差;随着梁、柱纵筋配筋率的增加,构件极限承载力及延性有所提升.

To explore the seismic performance of reactive powder concrete( RPC) beam-column joints,22 reactive powder concrete beam-column joints were analyzed by software ABAQUS.And hysteretic curves and skeleton curves of RPC beam-column joints were obtained. The factors affecting the hysteretic characteristics,ductility and bearing capacity of RPC beamcolumn joints were investigated,which included the axial compression ratio,the stirrup ratio of core joints,and the longitudinal reinforcement ratio of beams and columns. The results show that,RPC beam-column joints and high-strength concrete beam-column joints are consistent with the forcing behaviour rules. With the increase of axial compression ratio,the ductility of RPC beam-column joints decrease significantly. When the axial compression ratio lower than0. 6,the bearing capacity of components increase along with the axial compression ratio increase. However,the bearing capacity of components show a downward trend while the axial compression ratio exceed 0. 6. The stirrup ratio of core joints improve the bearing capacity and ductility of the components and delay the degradation of strength and rigidity. And bearing capacity and deformation capacity become poorer,when the stirrup ratio of core joints lower than1. 01%. With the longitudinal reinforcement ratio of beams and columns increasing,the ultimate bearing capacity and ductility of the components are improved to some extent.