Study On Dynamic Characteristics And Seismic Isolation Measures Of Twin Towers Anchored Suspension Bridge

At present,the anchored suspension bridge is widely used in bridge project for its unique shape.The first anchored suspension bridge in China began in 2000.Since 2015,the construction of more than 50 anchored suspension bridges has been carried out in China.With its unique appearance and excellent bearing performance,anchored suspension bridges have been included in the ranks of excellent bridge types by bridge designers.However,the study of damping adjustment and dynamic performance based on anchored suspension bridge is still not deep enough.In today's world,earthquake disasters are more and more frequent.Anchored suspension bridges lack specific criteria in the design of shock absorption regulation,so that they can be used for reference.Therefore,the research on the seismic dynamic warning and damping adjustment strategy based on the anchored suspension bridge is urgent to be carried out.This paper is based on Shenyang Dongta discussed across the muddy river bridge case.The analysis tool uses the bridge to design the Midas Civil general finite element software,which is the longest used at present.In this paper,the earthquake response of the Twin Towers anchored suspension bridge is analyzed and the vibration damping design is discussed.First,we should select the shape function that can express scientifically the natural vibration characteristics of anchored suspension bridge.Based on the Rayleigh method,we calculate the basic frequency of the lateral free vibration of anchored suspension bridge and the calculation formula of the vertical fundamental frequency of the anchored suspension bridge.Secondly,the synthetic seismic time history wave and design response spectrum(according to aseismic standard)are classified and input,and the two are treated as ground motions,so as to get the seismic responses of bridges.Then,the bending moment curves of stiffened girder,cable tower and main cable are studied.The similarities and differences between the data(equivalent yield bending moment)and the peak value of seismic response are analyzed,so as to get the seismic performance evaluation of the anchored suspension bridge in Twin Towers.Finally,the longitudinal and lateral seismic control of the bridge is carried out with viscous dampers,and the integrated planning of the reference data is used for reference.