轨道交通简支箱梁桥振动传递特性分析

摘要

基于某地铁高架线的简支箱型梁桥,建立轨道-桥梁振动传递特性分析模型,研究简支梁跨度、轨下刚度、桥上轨道结构形式以及箱型梁断面等因素对高架桥梁结构与噪声辐射相关的振动传递特性的影响.结果表明,简支梁跨度的变化不影响与噪声辐射相关的振动,而减振扣件可在90 Hz以上发挥减振降噪作用；加厚箱梁顶板和腹板能在一定程度上减小箱梁的振动和辐射噪声,用多腔室箱梁代替单箱室箱梁可显著减小振动及辐射噪声.分析结果可为城市轨道高架桥梁结构的设计和选择提供一定的理论参考依据.%Considering the simply supported box-girder bridges on urban rail elevated lines,a track-bridge dynamic model of vibration transmission was formulated.Effects of the span of simply supported box-girders,vertical stiffness of rail fasteners,track structures and the cross-section of box-girders on the noise radiation-related vibration of viaduct were studied.Results showed that the span of simply supported box-girder doesn't affect radiation-related vibration; reducing the stiffness of the fasteners can reduce the noise radiation-related vibration above 90 Hz; increasing the thickness of the roof and webs of girder section can reduce the vibration and noise radiation of the box girder; multiple chamber box-girders can significantly reduce the radiation-related vibration.Results of the study provided theoretical basis for the design and selection of viaduct structures in practical engineering design.