考虑减隔振装置非线性行为的无砟轨道桥梁噪声预测与控制

Noise pollution has become a bottleneck for the sustainable development of elevated lines in rail transit systems. It is very necessary to effectively control the bridge noise for the development of green traffic. In our previous studies, it was found that the load and frequency depended vibration isolation properties of rail fasteners have significant effects on the vibration energy transmitted to the railway bridges from the rails, and the granular dampers can be used as an inexpensive, durable and stable means of reducing the bridge vibration and noise. In this regard, three key scientific problems related to the nonlinearity within the vibration reduction and isolation devices are proposed to be studied: load and frequency dependence stiffness law of rail fasteners due to material and structural nonlinear properties of the fasteners; amplitude and frequency depended energy dissipation characteristics of gravel particle dampers owing to the contact nonlinearity, and nonlinear theory for the calculation of bridge vibration and noise. To solve these problems, simplified theoretical models of the fasteners and gravel particle dampers will be developed for the train-track-bridge-damper system coupling vibration analysis in the frequency-domain, by using the experimental and numerical methods. A noise prediction method will be then proposed based on the nonlinear vibration analysis of the system. An interactive control theory will be finally presented for bridge noise considering vibration isolation of the track, structural optimization of the bridge and vibration reduction of the particle dampers. Model experiments and field tests will be conducted for the verification and correction of the proposed prediction method and control theory for bridge noise. The research outcomes can be used to enhance theoretical foundation for the application of nonlinear vibration and noise reduction technologies such as gravel particle damping.

噪声污染是轨道交通高架线路可持续发展的瓶颈，对其进行有效控制是发展绿色交通的重大需求。申请人在前期研究中发现轨道扣件的载频变隔振特性对传入桥梁的振动能量有显著影响，砂石颗粒阻尼器可作为一种廉价、耐久、稳定的桥梁减振降噪装置。对此凝练出针对减隔振装置非线性行为的3个关键科学问题：材料与构造非线性引起的扣件刚度随荷载和频率变化的规律，接触非线性引起的砂石颗粒阻尼耗能特性随振幅和频率变化的规律，以及轨道桥梁振动和噪声的非线性分析理论。为此，结合试验和数值方法，建立适用于列车–轨道–桥梁–阻尼器系统耦合振动频域分析的轨道扣件和砂石颗粒阻尼器简化理论模型，形成基于系统非线性振动分析的桥梁噪声预测方法，发展考虑轨道隔振、结构优化及砂石颗粒阻尼器减振相互匹配的桥梁噪声控制理论。开展模型试验和现场实测研究，检验并修正所提出的噪声预测方法和控制理论，为砂石颗粒阻尼等非线性减振降噪技术的应用奠定理论基础。

噪声污染是制约高架轨道交通发展的主要瓶颈问题，对高架噪声进行准确预测和有效控制是发展绿色轨道交通的重大需求。本项目围绕轨道扣件载频变特性、颗粒阻尼器幅频变特性及高架桥梁噪声和轮轨滚动噪声综合预测模型、产生与传播机理和集成控制方法展开研究。主要研究内容及相应成果包括：1）改进了轨道交通扣件动刚度间接测试与分析方法，提高了测试精度和有效频率范围，建立了考虑扣件刚度载频变效应的弹簧-质量-弹簧结构理论模型；2）提出了多层耦合系统振动频域分析功率流方法，建立了合理的二维和三维声振耦合模型，发展了考虑扣件刚度载频变效应的轮轨噪声和桥梁噪声综合预测方法，揭示了扣件刚度载频变效应对高架轨道和桥梁振动、噪声的影响规律 ；3）设计了颗粒阻尼器试验耗能特性试验方案，建立了离散元数值模拟模型，揭示了钢球及砂石颗粒阻尼的耗能机理及耗能特性随振动频率和幅度的变化规律；4）提出了颗粒阻尼器等效理论模型，发展了考虑颗粒阻尼器的受控结构高频振动分析方法；5）建立了随机不平顺激励下车轨桥耦合振动分析模型，揭示了不平顺空间相干性及多个车轮间钢轨弯曲波的相干叠加机理；6）揭示了高架轨道交通桥梁噪声和轮轨噪声产生与传播规律，提出梁轨屏集成化噪声控制方法，开发了预制湿接长型浮置板新型结构，提出了采用回收颗粒橡胶的浮置板减振装置。研究成果应用于上海轨道交通18号线、宁波机场路南延工程公轨一体化双层高架桥及上海申昆路停车场上盖建筑等工程。已发表标注基金资助的学术论文20 篇，其中SCI 收录论文11 篇、EI 收录论文7篇、国际会议论文1篇。项目负责人在同济主办国内学术论坛1次。授权发明专利2项、软件著作权2项；培养已获得学位硕士生5人。项目负责人作为第3完成人获省部级科技进步奖一等奖1项。