Seismic Analysis Of The Earth-anchor And Steel Trussed Girder Suspension Bridge With Single-tower

Suspension bridge with single-tower is a common structure, which is widely used in railway and highway projects for its graceful appearance and well adaptability to different geological conditions. Suspension bridge is usually located in the key position of highway traffic network, and the impact which earthquake damage of suspension bridge with single-tower has on the post disaster relief operations and post disaster reconstruction is great. Therefore, it’s significant to conduct a conclusion of regularity from seismic analysis of the earth-anchor and steel trussed girder suspension bridge with single-tower to guide similar bridge designs.The paper is based on the Shaxian suspension bridge in Fujian Province and aims to study the seismic response of the earth-anchor suspension bridge with single-tower. The Shaxian suspension bridge is a steel trussed girder suspension bridge with single-tower, its main span is 112 meters. The steel trussed girder is a relatively new structural style.The Shaxian suspension bridge’s dynamic model is established with general finite element analysis software Midas Civil.And then the paper analyed its dynamic characteristic, response spectrum and time history analysis respectively. The partial content is as follows:Firstly, the paper introduces the development and seismic response analysis of suspension bridge in the domestic and overseas, and states the objects and content of the research.Secondly, this paper introduces the modeling process of dynamic calculating model of the Shaxian suspension and specifically analyzes the simulation of the main cable, the steel trussed girder, the main tower and boundary conditions of this bridge. The bridge alignment is recorded as well. The work on the impact of dynamic performance of the single-tower bridge as the change of stiffness of stiffened girder, tower and main cables provides the basis to the dynamic design of this system.Then, the paper introduces the requirement for fortification against earthquake and earthquake response spectrum analysis theory, the calculation of seismic action effect and combination methods. By referring to the related specifications, response spectrum analysis of suspension bridge with single-tower is conducted based on geological conditions. The internal forces of pier-tower bottom and displacement of tower top and girder mid-span are obtained through seven different input directions.Finally, time history response analysis is done, the results shows the Dynamic characteristics and seismic response of the suspension bridge with single-tower under different seismic waves and compares similarities and differences of response spectrum method and time-history method on the analysis of this kind of bridge.