磁流变阻尼半主动隔振浮置板轨道的动力非线性特征研究

In order to improve the increasingly serious environment vibration and noise generated by subway, a new damper (magneto-rheological damper) and a modern control theory (semi-active control theory) are introduced to further promote the anti-vibration capacity of subway track in our country. At first, to take the traditional steel spring floating slab track structure as reference, the vertical coupled dynamic model between subway vehicle and steel spring floating slab track with the vibration-isolation magneto-rheological damper would be established by using the vehicle-track coupled dynamics and the nonlinear dynamics of magneto-rheological damper. The established coupled dynamic model can be applied to explore the nonlinear vibration characteristics of floating slab track under random vertical irregularity excitation. Secondly, according to on-off groundhook control strategy, the semi-active control algorithm suitable for the nonlinear random vibration characteristics of floating slab track would be presented by comparison of some modern control algorithm, such as linear quadratic optimal control algorithm, optimal polynomial control algorithm, linear quadratic gaussian control algorithm and so on. After that, on the basis of numerical and experimental verification, the design procedures of floating slab track with the semi-active magneto-rheological damper would be proposed. The exploratory study would provide certain theoretical support and experimental experience for application of the new semi-active magneto-rheological damper control technology in subway vibration-attenuation track engineering.

为了改善我国地铁环境振动噪声日益严重的窘境，本项目拟借鉴新型阻尼材料（磁流变阻尼材料）与现代控制理论（半主动控制理论），来进一步提升我国地铁轨道的减振性能。鉴于此，首先以传统的钢弹簧浮置板轨道结构为参考型式，通过应用车辆−轨道耦合动力学理论与磁流变阻尼的非线性动力学理论，研究建立地铁车辆−磁流变阻尼隔振浮置板轨道的垂向耦合动力学模型，用以探讨轨道高低随机不平顺激励下磁流变阻尼隔振浮置板轨道的非线性振动特征；然后，借鉴经典的半主动开−关地棚控制策略，结合线性二次型最优控制算法、最优多项式控制算法或线性二次型高斯控制算法等现代控制算法，设计出适用于浮置板轨道非线性随机振动特征的磁流变阻尼半主动控制算法，继而在数值仿真与模型试验验证基础上，提出磁流变阻尼半主动隔振浮置板轨道的设计思路，为磁流变阻尼半主动控制新技术在地铁减振轨道工程中的应用提供一定的理论支撑与试验经验。

本项目以钢弹簧浮置板轨道为例，将新型阻尼材料（磁流变阻尼）与现代控制理论（半主动控制理论）共同引入钢弹簧浮置板轨道系统，进一步提升我国地铁轨道的减振性能。首先基于能量法的非线性参数识别方法，提出了磁流变阻尼修正的Dahl模型理论表征方法，为磁流变阻尼器在浮置板轨道中的应用提供了精确实用的动力学模型。基于车辆轨道耦合动力学理论与磁流变阻尼非线性动力学理论，依托传统的钢弹簧浮置板轨道结构型式，建立了地铁车辆磁流变阻尼隔振浮置板轨道垂向耦合动力学模型，分析了在不同激励下磁流变阻尼隔振浮置板轨道的非线性振动特性。然后借鉴经典的半主动控制策略，引入改进的Bang-Bang半主动控制策略，该控制方法可有效提高浮置板轨道固有频率处的减振；同时还解决了磁流变阻尼引起高频振动放大的问题。通过相关试验测试和理论建模分析，本课题研究出针对地铁低频减振效果的新型建振轨道结构型式，对我国城市轨道交通低频减振设计具有一定的参考价值。