Elastic Plastic Time History Analysis And Seismic Isolation Control Of The Irregular Ramp Bridges

The irregularity of the ramp bridges,such as the structural curvature and different pier height,which is obviously different from other types of bridges.At the same time,The ramp bridges generally have one or more consolidation piers.In the earthquake the complex loading states of pressure,bending,shear,and torsion in the consolidated piers of ramp bridges are induced.It has been found that the consolidated piers severely destroyed in past earthquakes.The ramp bridges are severely damaged by the earthquake and the main line will lose its original function.Therefore,it is of great significance to systematically study the seismic response of ramp bridges.As the object of this study,it is a ramp bridge from Boluo city to Longgang city.This paper studies the seismic response law of multiple parameters of ramp Bridge.The specific research work includes the following aspects:(1)Using the python language,a program was written to extract the results of ABAQUS.(2)The ABAQUS software was used to establish the finite element model of ramp bridge with different curvature radius and bridge pier height.Using the elastic plastic time history analysis method,the effects of radius of curvature and height of pier on the internal force,displacement,damage and reinforcement strain of piers were studied.(3)Multi-directional input seismic wave from 0 to 180 for a ramp bridge with a radius of curvature of 150 m,Studying the Influence of Input direction of Seismic Wave on the Internal force and displacement of bridge Piers(4)When the radius of curvature is 150 m,the seismic response of ramp bridge under different longitudinal slope was analyzed.The ramp bridge slope is 4%,change the radius of curvature,analyze the influence of radius of curvature on the ramp bridge under earthquake.(5)A finite element model of the ramp bridge using lead rubber bearings was established.By the elastic plastic time history analysis method,the influence of the parameters of longitudinal slope,radius of curvature and pre-yield stiffness of the bearings on the seismic isolation of lead rubber bearings was studied.