摘要
随着轨道交通行业的快速发展,轨道交通对沿线砌体结构的振动影响愈发显著,并存在振动局部放大的现象。通过建立车辆-轨道-隧道-地层-砌体结构耦合动力学模型,结合砌体结构模态分析,对某地铁线路临近1~6层砌体结构进行分析。结果表明:①当列车车型采取B型车、运行速度为60 km/h时,沿线低层(1~2层)砌体结构受地铁运行影响较小,较高层(3~6层)砌体结构出现振动响应放大现象;当砌体结构总层数为3~6层时,水平向振动加速度均在第2层取得最大值,第1层取得最小值。②从砌体结构模态分析结果来看,2~6层均在特定层数出现振动响应放大,且不同层数出现响应放大的振型频率范围在23~46 Hz之间,1层结构响应放大不明显。③砌体结构出现振动响应放大现象的振动频率与结构自振频率基本一致,且在此频率下,列车激振造成的楼层响应放大现象与自振模态中振动最大值出现的层数也基本一致,故列车荷载诱发砌体结构本身的自振,从而产生振动响应放大现象。
With rapid development of rail transit industry,effects of rail transit on vibration of masonry structures along rail line is more and more significant,and there is a phenomenon of local vibration amplification.Here,through establishing vehicle-track-tunnel-stratum-masonry structure coupled dynamic model,combined with masonry structure’s modal analysis,the masonry structure with 1-6 floors near a certain metro line was analyzed.The results showed that①when B-type train is adopted and its running speed is 60 km/h,the masonry structure of lower floors(1-2 floors)along the line is less affected by metro operation,the masonry structure of higher floors(3-6 floors)has vibration response amplification phenomenon;when the total floors of masonry structure are 3-6,the horizontal vibration acceleration reaches the maximum value at the 2 nd floor and the minimum value at the 1 st floor;②from the modal analysis results of masonry structure,vibration response amplification may occur at 2-6 floors,the frequency range of vibration response amplification occurring at different floors is 23-46 Hz,and vibration response amplification at the 1 st floor of the structure is not obvious;③vibration frequencies of masonry structure having vibration response amplification phenomenon are basically the same as natural frequencies of the structure,and under these frequencies,the floor where its response amplification phenomenon induced by train excitation occurring is basically consistent to the floor where its modal vibration maximum value occurring,so the train load induces natural modal vibration of masonry structure to cause vibration response amplification phenomenon.
作者
李政
金浩
郑军
LI Zheng;JIN Hao;ZHENG Jun(The Key Laboratory of Road and Traffic Engineering,Ministry of Education,Tongji University,Shanghai 201804,China;School of Transportation Southeast University,Nanjing 211189,China;Nanjing Metro Group Co.,Ltd.,Nanjing 210018,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2021年第15期263-270,共8页
Journal of Vibration and Shock
基金
国家自然科学基金(51908428)
上海市自然科学基金(19ZR1460400)。
关键词
地铁
轨道振动
砌体结构
模态分析
振动放大
subway
track vibration
masonry structure
modal analysis
vibration amplification
