预应力自复位节点有限元合理建模方法研究

Research on Reasonable Finite Element Modeling Methods for Prestressed Self⁃Centering Joints

预应力自复位结构具有良好的自复位性能,能显著降低震后的残余变形。节点的连接形式影响其自复位性能和抗震能力,为推动此类结构优化设计,需要大量研究分析工作和参数化分析,合理的建模方式可以更有效模拟出结构真实的受力情况。系统探讨了预应力自复位节点有限元分析中的核心问题,通过ABAQUS对内置耗能钢筋预应力自复位节点和角钢耗能预应力自复位节点试验数值模拟,得出结论:对于普通钢筋本构,使用滞回模型结果略好于双折线模型,但整体差异较小;降温法和MPC法均可以较好施加预应力,两者方法效果相同;虚筋法可以较好模拟出预应力筋的滑移,节点承载力和滞回曲线吻合度较高,同时工作量较耦合法和弹簧法更小。

Prestressed self⁃centering structures exhibit excellent self⁃centering capabilities,significantly reducing residual deformations after seismic events.The connection forms at the joints are critical to their self⁃centering performance and seismic resistance.To advance the optimization design of such structures,extensive research and parametric analyses are required.Appropriate modeling approaches can more effectively simulate the actual stress conditions of the structures.The core problems in the finite element analysis of prestressed self⁃centering joints are systematically discussed.The numerical simulation of prestressed self⁃centering joints with built⁃in energy⁃consuming steel bars and angle steel energy⁃consuming prestressed self⁃centering joints is carried out by ABAQUS.The following conclusions are drawn:for the regular reinforcement constitutive models,the use of hysteresis models yields slightly better results than the bilinear models,although the overall difference is small;both the cooling method and the MPC method can better apply prestress,and the effect of the two methods is the same;the virtual tendon method can better simulate the slip of prestressed tendons,with a high degree of agreement in joint bearing capacity and hysteresis curves,while also requiring less workload to the coupling method and the spring method.