基于磁悬浮理论的自适应抗拔摩擦摆隔震支座力学性能研究

Mechanical properties of the adaptive uplift-restraint friction pendulum bearing based on the magnetic levitation theory

为解决摩擦摆隔震支座抗拔能力不足的问题并优化其隔震性能,将传统的摩擦摆支座(FPB)和半主动控制思想相结合,提出一种自适应磁悬浮抗拔摩擦摆隔震支座(AMFPB)。基于磁路理论进行理论分析,推导出U型电磁铁的电磁力公式,以及AMFPB刚度、周期和等效阻尼比计算公式;对U型电磁铁进行位移-电磁力试验分析,建立AMFPB有限元模型,并对不同位移幅值、不同电磁铁匝数和输入电流下支座的滞回特性和抗拔性能进行分析。研究结果表明:U型电磁铁的位移-电磁力试验结果与理论结果吻合度较好,计算得到的AMFPB滞回曲线与数值模拟结果基本相同。AMFPB随滑动位移的增加可调节自身的刚度及耗能,有利于支座位移的控制。

The problem of insufficient pullout capacity in a friction pendulum bearing and the need to optimize its vibration isolation performance led to the proposal of an adaptive magnetic levitation uplift-restraint friction pendulum bearing(AMFPB).This novel solution was developed by integrating the traditional FPB with semi-active control concepts.A theoretical analysis of the AMFPB was performed based on magnetic circuit theory.The analysis resulted in deriving the electromagnetic force formula for the U-shaped electromagnet.Additionally,formulas for calculating the stiffness,period,and equivalent damping ratio of the AMFPB were established.To further validate these theories,a displacement-electromagnetic force test was conducted on the U-shaped electromagnet.Concurrently,a finite element model of the AMFPB was established to analyze the hysteretic characteristics and pullout performance of the AMFPB under different displacement amplitudes,electromagnet turns,and input currents.The displacement-electromagnetic force test results of the U-shaped electromagnet matched the theoretical findings.Moreover,the calculated hysteretic curve of the AMFPB closely mirrored the numerical simulation result.A standout feature of the AMFPB is its ability to adjust its own stiffness and energy consumption in response to an increase in sliding displacement.This unique characteristic makes the AMFPB advantageous in controlling bearing displacement.