Train-induced Vibration Analysis And Reduction Study Of Multi-tunnel Undercrossing Buildings

With the development of social economy and the continuous growth of population,the traffic situation of major cities becomes more and more serious.As an important means to alleviate this problem,rail transit got rapid development in recent years.However,the problem of vibration caused by rail transit system becomes more and more serious when it facilitates the travel of residents.In particular,with the innovation of design concept and the progress of construction technology,the major cities emerge a number of rail transit routes through existing buildings,which caused the problem of vibration is more prominent.Compared with a single line,the train running in multi-tunnel causes vibration of multiple vibration sources superimposed on the upper structure,thus resulting the upper structure in a complex vibration state.This kind of vibration causes more discomfort to the occupants,affect their normal life and work,thus resulting in lower applicable performance of buildings.Therefore,it is necessary to carry out reasonable vehicle vibration analysis and reduction study of multi-tunnel undercrossing buildings.In many damping measures,it is undoubtedly the most direct way to isolate vibration of the building by using vibration isolation bearing,in recent years the technology has been widely concerned by scholars.Due to the late start,there are few researches on the design of vibration isolation bearings and the corresponding theory of vibration isolation design,which still need to be further studied.Therefore,it is very important to carry out the vibration isolation design and analysis of vibration isolation bearing in the surrounding buildings along the rail transit.Aiming at the above problems,this paper takes a T3 terminal as the engineering background,mainly for the following work:(1)Based on the theory of vehicle-track coupling dynamics,the model of traintrack vertical interaction is established,and the train load is simulated by this model.(2)The three-dimensional finite element model of multi-tunnel-soil-building is constructed,and the dynamic response of the superstructure under different train running conditions is analyzed.The vibration characteristics and reaction behavior of multi-tunnel undercrossing buildings are obtained.(3)Aiming at the practical engineering of T3 terminal,the vibration response of the superstructure under train load is analyzed by establishing the two-dimensional finite element model of tunnel-soil-building.(4)A new isolation bearing is proposed to reduce the vertical train-induced vibration,and the vibration isolation design method is put forward.Taking a T3 terminal as the research object,the damping effect of the new vibration isolation support is analyzed.Finally,based on the summaries and conclusions of all research works,some suggestions and prospects for further research are put forward.