Vehicle-bridge Coupling Of Continuous Beam Bridge Under Impact Of Vehicle Jumping Vibration Response Analysis

With the development of modern transportation and logistics,vehicles are increasing day by day.Vehicles driving on bridges are a process of coupling.However,as bridges become old,there will be greater road unevenness and road obstacles.Vehicles running on uneven roads will complicate the coupling between the bridges.When the vehicle encounters road obstacles,the phenomenon of jumping will occur.The impact of jumping will further aggravate the vibration of the bridge.Regarding the impact of jumping and getting off the vehicle Most of the researches on bridge coupling vibration are based on simple beams or simply supported beams,which obviously cannot meet the requirements of modern bridge development.Therefore,this article is based on continuous beam bridges with variable cross-sections.First,establish a quarter model of the vehicle,use structural dynamics knowledge for theoretical analysis,and obtain the vibration balance equation of the vehicle,and then consider the geometric nonlinear factors of the bridge,establish the bridge vibration balance equation,and combine the two to apply to this article Calculated vehicle-bridge coupled vibration balance equation.Introduce the road irregularity expression method suitable for the calculation in this paper,and use Matlab programming to simulate the A,B,C,D level of road roughness.The vertical displacement response of the bridge under different pavement levels is calculated.As the unevenness of the road surface increases,the more the vertical displacement curve of the bridge jitters,the displacement amplitude also increases.Later,we calculated the response of car jumping,and calculated the coupled vibration response of the vehicle bridge at different car jumping heights.As the car jumping height increased,the peak mid-span displacement increased;when car jumping occurred in different spans,the car jumping span displacement occurred.The peak is the largest,and the farther from the jump,the smaller the peak.The moment when the peak occurs does not follow this rule;the coupled vibration response of the bridge under three different tire stiffnesses,and the three curves almost overlap;the coupled vibration response of the bridge under the suspension of different vehicles is studied,and the peak displacement of the bridge appears first with the increase of the suspension stiffness A tendency to decrease after increasing;B-class roads,near 20m/s speed,there are one or several speed-controlled resonance points,the vehicle jumps under this working condition,and the displacement peak value reaches the maximum;different vehicle weights are coupled to the bridge Vibration response,as the vehicle weight increases,the displacement response becomes larger,and the peak value of the mid-span displacement increases approximately linearly with the vehicle weight.This paper has carried out related research on the problem of considering the geometric nonlinearity of the bridge.The displacement response of the first span and the mid-span of the mid-span is studied when the geometric nonlinearity of the bridge is considered and ignored.The research shows that compared with ignoring the geometric nonlinearity of the bridge,considering the geometrical nonlinearity of the bridge The mid-span displacement in the nonlinear case is slightly smaller overall,and the difference is mainly manifested in the vehicle driving to the vicinity of the mid-span.Under the impact of jumping,this difference has a significant increase.