Study On The Influence Of Central Buckle On The Seismic Performance Of Different Stiffened Beam Suspension Bridges

After the central buckle is applied to the suspension bridge,the main beam and the main cable are buckled,which effectively improves the rigidity of the long-span suspension bridge.However,the research on the impact of setting the central buckle on the dynamic performance and seismic performance of the suspension bridge is still not comprehensive.Most of these studies are aimed at a single type of stiffening beam.And most of the previous studies did not take the traveling wave effect and nonlinear characteristics into account.Based on this,based on actual engineering,this paper establishes suspension bridge models with different stiffening beam forms,studies the stiffness improvement and dynamic performance and seismic performance changes of suspension bridges with different stiffening beam forms after setting different central buckles,and different structural stiffness of stiffening beams is also different,use this as a variable to compare the effect of the central buckle on suspension bridges with different stiffness.The main research contents are as follows:First,the static analysis theory of the suspension bridge is discussed,which includes calculations under vertical,horizontal,and eccentric loads.It also introduces several commonly used seismic analysis methods for bridges,and elaborate on the theoretical basis and numerical solution methods of Time-history analysis.Explained in detail the necessity of taking into account the nonlinear characteristics and traveling wave effects in the analysis of suspension bridges and determined the method used to achieve the traveling wave effect.Then,the finite element models in the form of steel box stiffening beams,steel truss stiffening beams and prestressed concrete plate stiffening beams were established,and each type of suspension bridge model of stiffening beams is distinguished from no central buckle,flexible central buckle and rigid central buckle.Conduct static analysis and modal analysis,preliminary understand the relationship between the stiffness of different stiffening beam models,and summarize the impact of the central buckle on the dynamic performance of each model,to provide a basis for further timehistory analysis.Finally,select the appropriate seismic wave according to the site conditions and the vibration characteristics of the structure itself,and make the peak value reduction and baseline adjustment of the seismic wave to ensure the reliability of the calculation results.Input the selected seismic wave into the model for longitudinal and transverse bridge direction Time-history analysis,comparing the corresponding earthquake situation with flexible and rigid central buckle and without central buckle under each stiffening beam form,summarizes the influence of the central buckle on the seismic performance of each stiffening beam suspension bridge model.Then,it compares and analyzes the regularity of the influence amplitude caused by the flexible and rigid central buckles as the rigidity of the suspension bridge changes.