Analysis Of Seismic Response Of Curved Continuous Rigid Frame Bridge With Corrugated Steel Web In High Intensity Area

With the further development of western China,the construction of highway and railway in western China has also ushered in a new development opportunity.However,in the western region of China,there are many valleys and rivers.In order to cross these natural barriers,it is necessary to build many bridges.Due to the limitation of the terrain,and to meet the design requirements of flat and vertical sections,curved bridges are favored by engineers with their smooth linear features.And most of the seismic zone of our country is distributed in the western region,where earthquakes happen frequently and most of the area belongs to the high intensity area,so the study of the dynamic characteristics and seismic response of curved continuous rigid frame bridge in high intensity area is of great significance to better guide the engineering practice,and also can cause the curved continuous rigid frame bridge in the western region for a wider range of applications.This paper analyzes a curved continuous rigid frame bridge with corrugated steel web in western China,and its main work is as follows:(1)Establish the model that considers the pile-soil-structure interaction and the model that does not consider the pile-soil-structure interaction respectively,and analyze the dynamic characteristics of the structure based on the established model,and study the influence of pile-soil-structure interaction on the natural vibration characteristics of curved continuous rigid frame bridge.(2)Establish the models of different radius of curvature and study the influence of the curvature radius to the natural vibration characteristics of the bridge.Compare the natural vibration characteristics between the curved continuous rigid frame bridge and the straight bridge,and observe its natural vibration modal distinction,analysis the influencing factors leads to the differences between curved bridge and straight bridge from the aspects of its structure characteristics of curved bridge.(3)When conducting seismic response analysis of straight bridge,there are two clear main directions.Generally,the analysis can be carried out along these two directions.However,a curved bridge does not have a clear main direction.Therefore,based on the response spectrum theory,this paper analyzes the influence of ground motion input angle on the seismic response of curved continuous rigid frame bridge by changing the angle of ground motion input,and discusses the most unfavorable angle of ground motion input of the curved continuous rigid frame bridge.(4)By time history analysis method,discuss the seismic response rules of E1 and E2 of the curved continuous rigid frame bridge under ordinary earthquake.The seismic response laws of E1 and E2 of the curved continuous rigid frame bridge under near-fault earthquake with velocity pulse are discussed.The difference of seismic response under these two types of earthquakes is compared and analyzed,and the influence of the velocity pulse effect of near-fault earthquakes on the seismic response of curved continuous rigid frame bridge is analyzed,and the nonlinear analysis under E2 earthquake is carried out to discuss the development law of plastic hinge.(5)Compare and analyze the isolation effect of cable basin bearing on curved continuous rigid frame bridge by time-history analysis method,analyze the influence of cable stiffness and initial gap on the isolation performance of cable basin bearing,and determine the reasonable support parameters.