Dynamic Response Analysis Of Curved Bridge Under The Vehicle-Bridge Coupling

So much extensive attention has been paid to the dynamic response research of bridge under moving vehicle load.The research results of Railway Bridge have been embodied in the design codes,while it is not perfected in the design codes of Highway Bridge.In recent years,the curved bridge is widely applied.Because it can adapt to the restriction of various routes and meet the people’s requirements of beauty.But the structure of curved bridge is different from the straight bridge,so it is very important to study the influence of vehicle load on the dynamic response of curved bridge.In view of this,this paper,taking a curve continuous box girder in Jiangxi province as the research object,has studied its dynamic response under vehicle load.The main work and achievements are as follows:(1)Based on the solid45 solid element in ANSYS,a finite element model of the four-span continuous curved box girder was established,and the vibration equations of the four degrees of freedom and nine degrees of freedom vehicle were derived based on the D ’Alembert principle.(2)The surface roughness was introduced to simulate the irregularity of the bridge surface.Based on Matlab/Simulink,the simulation model was built.The filter white noise method was adopted to simulate the uneven curve of A-D road surface according to national standard GB/ T7031-86.(3)The curve bridge model and vehicle vibration equation of two subsystems are connected by the wheel and bridge deck of the displacement coordination relation and force balance relationship,the vehicle-bridge coupled model is established.The accuracy of the vehicle-bridge coupled model is verified by comparing the simulation results with the literature data and field test data.(4)Based on the vehicle-bridge coupled model,the influences of vehicle centrifugal force,vehicle speed,vehicle load,and eccentric driving of vehicle on the dynamic response of curved bridge are discussed.The results show that the midspan torsion angle is increased and the torsion trend of curved bridge to the outside is increased because of the centrifugal force.With the increase of vehicle speed,the vertical displacement,the torsion angle and stress of the midspan increase first and decrease later,while decrease with the increase of the radius of curvature.The dynamic response of curved bridge increases linearly with the increase of vehicle load.During the eccentric driving of the vehicle,there is a empty phenomenon in the middle support.The dynamic response of curved bridge increases with the grade of road surface changing from good to bad.