Vibration Response Analysis Of High-Speed Rail Station Structure Under Train Load Excitation

High-speed railway,with its high speed,low power consumption,large transport volume,little pollution and high security,quickly became the main tool of modern transportation.However,when high-speed railway brings people a lot of convenience,it also causes environmental vibration problems to the residents along railway lines.Under this background,this paper carried out an in-depth study of the vibration responses of the station structure under high-speed train excitation.This paper bases on the engineering background of the Chongqing shapingba integrated transport hub project.The vehicle-track model,the track-soil model and the station structure model are established using finite element method,by which the vibration responses of the station structure and platform are calculated.The reasonableness of the modeling method is verified by the measurement of the vibration of Chengdu to Dujiangyan fast railroad.According to the vibration responses of the station structure,the analysis is divided into 3 categories with 13 conditions,in order to fully investigate the vibration responses of the station structure under high-speed train excitations.In addition,the effects of fastener stiffness and damping pad stiffness influence on the vibration response of the station and the platform are compared.The main conclusions are as following:(1)Under different conditions,the dominant vibration frequencies of station platform is 20Hz～63Hz and the peak frequency concentrated in about 40Hz;the dominant vibration frequencies of the station is 10Hz～63Hz,and the peak frequency at each texting point concentrated in about 40Hz,which is consistent with the frequency spectrum of wheel rail force.(2)When the train passes through arrival-departure line:The train passes through track 6,7 at the same time,the vibration responses of the station platforms are the largest and the largest vibration appears at the platform 3;The train passes through track 1,2 at the same time,the vibration responses of the station platforms are the smallest.The maximum vibration of the station structure appears when the train passes through track 2,3 and the smallest vibration of the station structure appears when the train passes through track 6,7.(3)When the train passes through lines connecting main line,impacts that caused by the arrival-departure line to station structure and platform is negligible and only the vibration caused by the lines connecting main line is considered.When the train passes through track 4,5 at speed 220km/h,the vibration of the station structure and platform is under the limit;when the train passes through arrival-departure line at speed 70km/h,the vibration of the station structure and platform meets the required specification limits.(4)The increase of fastener stiffness can effectively reduce the vibration response of the platform and the station in the frequency range of 6.3～31.5Hz.Damping pad can effectively weaken vibration in the frequency range of 12.5～80Hz,and when damping pad stiffness is 2.5×106N/m,the vibration reduction of the station is the best.