摘要
以深圳某带上盖建筑地铁车辆段为工程依托,现场实测了咽喉区列车走行不同线路时,地面层、平台转换层和上盖4层钢框架结构的振动加速度响应,分析了咽喉区列车运行引起的环境和结构振动传播规律。研究结果表明:由于土-结构的动力相互作用,车致振动在从地基土向基础结构的传播过程中存在能量损失,实测结构基底加速度幅值较邻近地面加速度幅值显著减小;车致振动在从地基土向结构的传播过程中,50 Hz以上高频分量衰减更为迅速,土-结构耦合损失最高可达27~34 dB,因此,基于子结构法,采用基底输入预测地铁车辆段上盖建筑车致振动响应时,应考虑土-结构耦合损失的影响,宜采用平台立柱基底振动作为模型振动输入;上盖平台与转换层的结构设计能够在一定程度上减弱车致振动的向上传播,加速度级衰减幅度为3~6 dB;车致振动以轴向波的形式通过平台立柱向上传播,并以弯曲波的形式通过转换梁和楼板水平扩散,振动能量有多条传播路径传至上盖建筑并进行叠加,平台转换层各测点振动差异在8 dB以内;上盖建筑层间的振动传播规律取决于梁和楼板与竖向承重结构的阻抗比,增大梁或楼板的阻抗有助于减弱振动的向上传播;该上盖4层钢框架结构实测车致振动频率存在3个峰值,分别为6.3、12.5和40.0 Hz,其与结构固有频率和激励动力特性有关。
Relying on a metro depot with over-track buildings in Shenzhen,the vibration acceleration responses during trains passing on different tracks in the throat area were measured on-site at the ground floor,platform transfer floor,and the over-track 4-storey steel-framed structure.The propagation laws of environmental and structural vibrations caused by train operations in the throat area were analyzed.Research results show that there exists energy loss when the train-induced vibration propagates from the surrounding soil to the foundation through the soil-structure dynamic interaction.The measured acceleration amplitude at the foundation bottom of the structure is significantly smaller than that at the adjacent ground surface.In the process of train-induced vibration propagation from the surrounding soil to the structure,the high-frequency component above 50 Hz attenuates more rapidly.The soil-structure coupling loss can be up to 27-34 dB.Therefore,the influence of soil-structure coupling loss should be considered when using the foundation bottom inputs to predict the train-induced vibration responses within the over-track buildings at metro depots based on the substructure method.The vibrations at the foundation bottom of the platform columns should be used as the vibration input of the model.The structural designs of over-track platform and transfer floor can help to reduce the upward propagation of the train-induced vibration to some extent.The acceleration level attenuation amplitude is 3-6 dB.The train-induced vibration propagates upward through the platform columns in the form of axial wave and spreads horizontally through the transfer beams and floor slabs in the form of bending wave.The vibration energy has multiple paths to propagate toward the over-track building and superpose.The vibration difference among measuring points on the platform transfer floor is within 8 dB.The vibration propagation law between floors in the over-track building depends on the impedance ratios of beam to vertical load-bearing st
作者
汪益敏
陶子渝
邹超
陈颖
WANG Yi-min;TAO Zi-yu;ZOU Chao;CHEN Ying(School of Civil Engineering and Transportation,South China University of Technology,Guangzhou 510641,Guangdong,China;School of Civil and Transportation Engineering,Guangdong University of Technology,Guangzhou 510006,Guangdong,China)
出处
《交通运输工程学报》
EI
CSCD
北大核心
2022年第1期112-121,共10页
Journal of Traffic and Transportation Engineering
基金
国家自然科学基金项目(51908139)
广东省科技计划项目(2017A050501005)
广东省基础与应用基础研究基金项目(2021A1515012605)。
关键词
地铁车辆段
现场试验
振动
传播规律
上盖建筑
metro depot
field test
vibration
propagation law
over-track building
