Dynamic Response Analysis Of Steel Plate Composite Beam Bridge

In this paper,the Laowucun steel plate composite girder bridge is taken as the research object.The bridge modeling was carried out by ANSYS;The dynamic response characteristics of steel plate composite beams considering pile-soil interaction are studied.The dynamic response of steel plate composite beams under seismic loading is studied by the combination of frequency domain analysis and time domain analysis.Based on the internal force,displacement,velocity and acceleration response of the steel plate composite beam,the effects of vertical earthquake and pile-soil interaction on the seismic response of the composite steel beam are studied.Considering that the bridge is mainly subjected to the dynamic load of the vehicle after it is built.In this paper,the dynamic response of steel plate composite beams under different vehicle weight and speed is studyed from structural internal forces,main beam deflection,speed,etc.The main research work of this paper is as follows:(1)This paper reviewed the basic method for seismic response analysis of bridges such as static analysis method,frequency domain analysis method and time history analysis method.At the same time,The dynamic response analysis methods for bridge moving loads such as uniform velocity constant force,uniform velocity mass,uniform velocity harmonic force,and uniaxial and multiaxial analysis theory methods are reviewed.At the same time,the vehicle-bridge coupling simulation is briefly introduced.(2)The refined solid model is established for the steel plate composite girder bridge,and the dynamic characteristics of the structure under consideration of the interaction between the pile and the soil are compared and analyzed.The research shows that the pile-soil interaction has a great influence on the displacement,velocity,acceleration and internal force of the steel plate composite beam,which can not be ignored in the seismic response research;In order to study the influence of vertical earthquake on the bridge structure,the concentrated mass model considering pile-soil interaction is used to analyze the multi-case seismic response of the steel plate composite girder bridge from frequency domain and time domain analysis.The research shows that under the vertical earthquake,the internal force of the composite beam structure increases to a certain extent.Among them,the vertical earthquake has a greater influence on the axial force of the structure,and has less influence on the bending moment and shearing force of the structure.In addition,the vertical direction Earthquakes also increase the displacement of the structure by about 10%;(3)The vehicle load is simplified to uniform constant force,and this method is used to simulate the coupling of the 25m simple supported beam bridge,and the obtained results are compared with the analytical solution.The research shows that the results obtained by simulating the vehicle load with uniform constant force are well fitted with the analytical solution,which proves the feasibility of the simulation method and the accuracy of the simulation results.Using uniform velocity and constant force to simulate the vehicle’s action to simulate the dynamic response of the steel plate composite beam under different vehicle speeds.The results show that when the vehicle speed is small,the vehicle speed has little effect on the steel plate composite beam.When the vehicle speed reaches 220km/h,the deflection and speed of the steel composite beam point increase linearly with the increase of the vehicle speed.Using uniform velocity and constant force to simulate the vehicle’s action to simulate the dynamic response of bridges under different vehicle weights and make a comparative analysis.The research shows that the influence of vehicle speed on the deflection of each point of steel plate composite beam increases linearly.When the vehicle weight is less than 40t,the weight of the vehicle has little effect on the speed and acceleration of each point of the bridge structure.When the vehicle is more than 40t,the structure is different.The point speed and acceleration value increase greatly.In addition,the weight of the vehicle has little effect on the upper edge stress of the steel plate composite beam,but the lower edge stress has a greater influence and basically increases linearly.