摘要
The human-induced vertical vibration serviceability of low-frequency and lightweight footbridges is studied based on the moving mass-spring-damper（MMSD） biodynamic model, and the mass damper（TMD） with different optimal model parameters being used to control the vertical vibration.First, the MMSD biodynamic model is employed to simulate the pedestrians, and the time-varying control equations of the vertical dynamic coupling system of the pedestrian-bridgeTMD are established with the consideration of pedestrianbridge dynamic interaction; and the equations are solved by using the Runge-Kutta-Felhberg integral method with variable step size. Secondly, the footbridge dynamic response is calculated under the model of pedestrian-structure dynamic interaction and the model of moving load when the pedestrian pace frequency is consistent with the natural frequency of footbridge. Finally, a comparative study and analysis are made on the control effects of the vertical dynamic coupling system in different optimal models of the TMD. The calculation results show that the pedestrian-bridge dynamic interaction cannot be ignored when the vertical human-induced vibration serviceability of low-frequency and light-weight footbridge is evaluated. The TMD can effectively reduce the vibration under the resonance of pedestrian-bridge, and TMD parameters are recommended for the determination by the Warburton optimization model.
基于移动质量-弹簧-阻尼(MMSD)生物动力学模型,研究了低频轻质人行桥的竖向振动舒适度,采用不同优化模型参数的调谐质量阻尼器(TMD)对其进行振动控制.首先,采用MMSD生物力学模型模拟行人,建立考虑人-桥动力相互作用的人-桥-TMD竖向动力耦合系统的时变控制方程,利用变步长的RungeKutta-Felhberg算法对控制方程进行求解.其次,探讨行人步频与人行桥频率一致时,人行桥在人-结构动力相互作用模型和移动荷载模型下的动力响应.最后,采用TMD对人行桥进行振动控制,对比分析不同优化模型的TMD对人-桥竖向动力耦合系统的控制效果.计算结果表明:评估低频轻质人行桥竖向振动舒适度时,人-桥竖向动力相互作用不容忽视;采用TMD能够有效地减轻人-桥共振时的人行桥振动,TMD参数建议依据Warburton优化模型确定.
基金
The National Natural Science Foundation of China(No.51508257,51668042,51578274)
the Yangtze River Scholar and the Innovation Team of M inistry of Education(No.IRT13068)
the Scientific Research Project of Gansu Higher Education(No.2015B-34)
