Vibration Characteristics Analysis And Vibration Isolation Research Of Metro Depot Over-track Buildings

Urban rail transit has the advantages of high transportation efficiency,safety,convenience and environmental protection.In recent years,it has developed rapidly in China.The utilization efficiency of urban land resources can be improved by utilizing the upper space of Metro Depot to develop property.The advantages of metro transportation can be brought into full play.The train of Metro Depot runs between the columns of the upper structure,and the vibration induced by the train runs directly through the columns.When it spreads to the superstructure,the vibration attenuation is small and contains abundant high frequency vibration.The environmental vibration problem is very prominent,which becomes one of the bottlenecks restricting the development of the superstructure property of Metro depot.At present,the research on vehicle-induced vibration of the superstructure of Metro Depot is not perfect.For the fast loading section,it is necessary to further analyze the vibration characteristics of the superstructure of Metro depot,and to take reasonable vibration reduction measures to reduce the vibration impact of train operation on the superstructure.In view of the above problems,this paper studies the vehicle-induced vibration of the over-track building of a depot test line by field measurement,establishes a three-dimensional refined finite element model of the over-track building building for numerical simulation and analysis,and uses a new type of thick rubber vibration isolation bearing to isolate the vibration of the over-track building of a metro.The main work is as follows:(1)The vehicle-induced vibration of the superstructure on the test line of Metro Depot is tested.Based on the environmental excitation,the dynamic characteristic parameters of the superstructure floor are identified.The vibration propagation law and vibration characteristics of the superstructure under different train loading speeds are analyzed,and the vehicle-induced vibration of the superstructure is evaluated according to the vibration evaluation criteria.(2)According to the design parameters,a three-dimensional refined finite element model of metro vehicle depot covers is established,and the dynamic response of the over-track buildings under train load is analyzed,and compared with the measured results.On this basis,the dynamic characteristics of the structure caused by the attributes of building materials,construction errors,space modification of buildings and distribution of live loads are reasonably considered.The effects of damping ratio,beam-slab size,concrete strength,partition constraints and equivalent mass of live loads on the dynamic characteristics and vehicle-induced vibration of the floor in the upper building of a depot are analyzed.(3)Because the vibration of the Metro superstructure induced by the train running on the test line exceeds the norm limit,a new type of thick rubber vibration isolation bearing is arranged on the platform layer of the depot to reduce the vibration of the superstructure.The parameters of the new type of vibration isolation bearing are designed in combination with practical engineering.The vibration isolation effect of the vibration isolation bearing is analyzed by numerical analysis method,and the frequency and damping ratio of the vibration isolation layer are studied.The effect of vibration isolation.