粘弹性支座对高架轨道桥梁竖向车致振动的减振影响研究

In order to prevent the vibration pollution of elevated rail transit, a new kind of high damping rubber anti-vibration bearing is proposed to investigate the problem of damping effect under moving loads for this kind of flexible support. It is useful to ensure the quality of vibration environment for people’s normal life, work and study, protect the existing cultural relics, guarantee the normal use of precise instruments in the sensitivity area of vibration and promote the progress of vibration control technology for the elevated rail transit. With the characteristics of low stiffness and high damping, such a kind of anti-vibration bearing is different from a common bearing. It will change the inherent dynamic characteristics of elevated bridge. Meanwhile, the structural dynamic analysis under moving loads is also different from that under seismic action. As the structure keeps in elastic state under moving loads, the contributions of non-structural components and other factors to the dynamic characteristic of the elevated bridge cannot be neglected. Therefore, this investigation should be separated from the traditional vehicle-bridge coupling vibration analysis..This project will be carried out by means of the combined method of theoretical analysis, numerical simulation and field measurement. The train-induced vibration response of the vehicle-bridge interaction system under the boundary condition of flexible support is solved through theoretical analysis. A refined structural analytic model under the condition of weak vibration is established and modified on the basis of the measured data. The rules about the influence of the vehicle-bridge coupling vibration analysis and vibration propagation are discussed to the viscoelastic bearing by numerical simulation. Based on the measured data, the damping effect of different bearing types is comparatively analyzed and the range of stiffness and damping parameters of anti-vibration bearing is cleared. The research results are significant to guide the design and optimization of anti-vibration bearing.

为防治高架轨道交通振动污染，保证人们正常生活、工作和学习的振动环境质量，保护既有文物古迹，保障影响区域内精密仪器正常使用，促进振动控制技术进步，拟提出一种高阻尼橡胶减振支座并研究其减振效果。与普通支座不同，此减振支座具有低刚度和高阻尼特点，会改变高架桥梁的固有动力特性；且与地震作用下的结构动力分析不同，在列车荷载作用下，结构处于线弹性状态，非结构构件等因素对动力特性的影响不可忽略，因而应与传统的车桥耦合振动分析有所区别。.拟采用理论分析、数值模拟和试验测试相结合的方法开展研究：理论分析求解柔性支承边界条件下车桥相互作用系统的振动响应；建立弱振下精细化的桥梁结构模型并基于实测数据进行修正，数值模拟分析粘弹性支座对车桥耦合振动分析与振动传播的影响规律；基于实测数据，分析不同支座类型的减振效果并明确减振支座刚度和阻尼参数的取值范围。研究结果对于桥梁减振支座的设计和优化具有重要指导意义。

随着城市轨道交通的飞速发展，高架轨道交通作为轨道交通的一种主要结构形式，连接着主要城市或区域，在公共交通运输中起着重要的作用，但是也造成了严重的环境振动问题。为防治高架轨道交通振动污染，保证人们正常生活、工作和学习的振动环境质量，保护既有文物古迹，保障影响区域内精密仪器正常使用，促进振动控制技术进步，提出了具有低刚度、高阻尼特点的新型减隔振装置。该减振支座与普通支座不同，可以改变高架桥梁的固有动力特性，影响高架桥梁的车致振动及其传播规律，导致与传统的车桥耦合振动分析有所区别。.本项目重点研究粘弹性支座对高架轨道桥梁竖向车致振动的减振影响规律。通过理论分析建立了柔性支承对桥梁结构车致振动分析的简化计算方法，揭示了粘弹性支座对高架轨道桥梁车致振动的影响规律，推导了粘弹性支承梁在移动荷载及移动荷载列作用下的动力响应解析解，明确了桥梁支座刚度和阻尼参数对车致振动的影响。通过数值分析建立了弱振下高架桥梁的精细化有限元模型，结合实际工程现场实测，分析了各种因素对高架桥梁车致振动的影响规律，同时，研究了不同桥梁支座对高架桥梁车致振动的减振影响，提出了一系列具有低刚度、高阻尼特点的新型减隔振装置，且通过试验验证了新型橡胶减振支座的减振效果。.研究成果可拓展车桥耦合振动理论，也可作为环境振动控制措施服务于工程实际来改善环境振动质量，对于桥梁减振支座的设计和优化具有重要指导意义。