Study On Buckling Restrained Brace Design And Sesimic Performance Of Continuous Beam Bridge

The new building seismic design code has improved the seismic fortification intensity in some areas and put forward new requirements for the seismic performance of the existing buildings.As an important transportation hub,The bridge has a pivotal role in the process of rescue and disaster relief,so to improve the seismic performance of the bridge has become a hot research problem.Buckling Restrained Brace is a new type of energy dissipation components,which has the advantages of taking precedence over the main structure of the first yield,high bearing capacity and stable mechanical performance.It is widely used in the building structure,but a little in the bridge.In this paper,the method of Buckling Restrained Brace bidirectional placement has put forward to control lateral and longitudinal displacement of the bridge,improve the seismic performance of bridge in both directions.This paper chooses one of the three-span continuous-beam viaducts as the research object.Firstly,according to the stability theory of Buckling Restrained Brace,the simplified design flow of Buckling Restrained Brace in continuous beam bridge has been put forward,and the Buckling Restrained Brace has been designed according to the structural design flow and the structural requirement of buckling.Secondly,the finite element model of the continuous beam bridge is established by finite element software Midas,and the results of the self-vibration characteristics of the original structure and the Buckling Restrained Brace structure have been compared and analyzed.Finally,five cases have been set up to compare the supporting force and the seismic performance of the bridge under different supporting arrangement and length.The results show that the Buckling Restrained Brace has a good shock absorption effect,which can control the longitudinal and lateral displacement of the bridge and reduce the seismic effect of the bridge.The Buckling Restrained Braces is more economical and reasonable,The length of the Buckling Restrained Braces has a certain influence on the seismic performance of the bridge,and the optimal support length is selected by contrast analysis.