基于伸臂-负刚度阻尼原理的应力带桥减振控制研究

Vibration Control of Stress-ribbon Bridge Based on Outrigger-Negative

随着城市建设水平的提高和旅游业的发展,对大跨人行景观桥建设需求不断增加。应力带桥因具有简洁的结构形式和优美的建筑外观,被逐渐应用于人行景观桥中,但其固有频率低、模态间隔紧密,在风、行人等动荷载作用下易发生振动。因此,为控制应力带桥振动,提出了基于伸臂-负刚度阻尼原理的应力带桥减振控制策略。首先,基于欧拉-伯努利梁理论建立了系统广义运动方程,并提出了基于复模态的系统动力特性计算方法。其次,系统地研究了应力带桥负刚度控制系统关键参数对系统动力行为的影响规律,并确定了关键参数设计准则。最后,基于案例分析对比验证了所提控制策略对应力带桥人致振动控制的有效性。提出的应力带桥减振控制方法与相应参数确定准则可为实际工程中应力带桥的建设提供参考。

With the improvement of urban construction level and the development of tourism industry,the demand for the construction of large-span pedestrian landscape bridges continues to increase.Stress-ribbon bridges are gradually applied in the pedestrian landscape bridges because of their simple structural form and beautiful architectural appearance.However,they are prone to vibration under dynamic loads such as wind and pedestrians due to the low natural frequency,tight modal spacing.Therefore,based on the outrigger-negative stiffness damped principle,a stress-ribbon bridge vibration reduction control strategy is proposed to control the vibration.Firstly,the generalized motion equation of the system is established by the Euler Bernoulli beam theory.And a method for calculating the dynamic characteristics of the system based on complex modes is proposed.Secondly,the influence of key parameters of the stress-ribbon bridge negative stiffness control system on the dynamic behavior of the system is systematically studied,and the design criteria for key parameters are determined.Finally,the effectiveness of the proposed control strategy for stress band bridge induced vibration control was verified through case analysis and comparison.The proposed stress-ribbon bridge vibration reduction control method and corresponding parameter determination criteria can provide reference for the construction of stress band bridges in practical engineering.