Analysis Of Dynamic Characteristics And Seismic Response Of Curved Rigid Frame Bridge

With the ever-accelerated development of transportation in China,the span and pier height of continuous rigid-frame bridges have been increasing.Owing to the requirement of linear route and the limitation of terrain conditions,more and more curved continuous rigid-frame bridges with high piers and long spans are being built.Compared with medium and small span bridges,the seismic response and seismic design of high pier and long span curved continuous rigid-frame bridge are more complicated.Up to now,more detailed theoretical research has been carried out on curved bridges in the engineering field.Many scholars have established many simple and practical calculation methods in combination with the knowledge of many disciplines for the required theoretical research.However,there are few researches on the dynamic characteristics of curved bridges,especially on the characteristics of curved bridge structures under earthquake response.Based on the above background,the following researches had been conducted in the paper.Firstly,there was an introduction to the curved rigid-frame bridge and its structural characteristics as well as research status of seismic bridges.This paper gave a presentation of the basic theory and analysis method of curved girder bridge with emphasis on the widely used dynamic response spectrum method,dynamic time history analysis method and the selection of seismic waves.Taking a curved continuous rigid-frame bridge with the span of 90m+180m+90m in Sichuan province as an example,this paper established calculation model of the bridge of spatial finite element dynamic,and made an analysis on the dynamic characteristics of it.A plurality of variable parameter models were established,and the dynamic response spectrum analysis method was adopted to analyze the seismic response of structures with different curvature radius and different seismic excitation directions as well as the seismic response of structures with different pier heights and different seismic excitation directions,and to study the seismic response of high-pier and long-span curved continuous rigid-frame bridges with different influencing factors.Finally,this paper gave a summary of the work done and drew some correspondingconclusions,which provided useful reference for the seismic design and research of the same type of bridges,and puts forward the prospects for the deficiencies in the research process.