Seismic Response Analysis Of High Pier Long Span Continuous Rigid Frame Bridge In Wolonggou

With the vigorous development of national economy and the remarkable progress of social civilization,the convenience and smoothness of transportation plays an increasingly important role.Therefore,the traffic line has become the lifeline of the country and the society,and the bridge as the skeleton of the traffic line is the most important.The continuous rigid frame bridge with high pier and large span is favored by bridge workers in the southwest and northwest regions of China where there are many high mountains and deep valleys and wide rivers and rapids,depending on its advantages of reasonable economy,beautiful appearance,convenient construction and superior crossing ability.Since China is located between the Pacific rim seismic belt and the Eurasian seismic belt,there are many earthquakes.It is very important to study the seismic response analysis and seismic performance of bridges.Compared with ordinary medium and small Bridges,the seismic response of continuous rigid frame Bridges with high piers and large spans is more complex,so it is necessary to study the seismic resistance of this kind of bridge.This article first introduces the seismic damage of the bridge,and the development and research status of prestressed concrete continuous rigid frame bridge are discussed,and then expounds the methods of the seismic response analysis of bridge structure.Taking the main bridge(75+140×3+75)m continuous rigid frame bridge of wolonggou 3 bridge as the research background,the finite element software is used to analyze its seismic response.The main research contents are as follows:(1)The finite element software Midas Civil is used to establish two calculation models: pier-bottom consolidation model and pile-soil-structure interaction model,and to explore the dynamic characteristics of continuous rigid frame bridge.The effect of pile-soil action on the inherent characteristics of the structure and the action of high-order mode on the dynamic calculation are discussed.(2)By selecting three actual seismic waves and using pile-soil-structure model,the linear and nonlinear seismic responses of bridge structures under E1 and E2 earthquakes are analyzed by using bidirectional and tridirectional orthogonal excitation methods.Under the action of E1 and E2 earthquakes,the structural responses of three seismic waves are compared,and the difference between linear analysis and nonlinear analysis is explored.The effect of vertical seismic excitation on structure is studied by comparing the results of bidirectional and tridirectional orthogonal excitation.The occurrence and development of plastic hinge of pier are discussed,and the possible locations of plastic hinge of rigid frame bridge with high and low pier are extended and analyzed.(3)The traveling wave effect of the bridge with different apparent wave velocities is analyzed by using the large mass method.The development law of bridge displacement and internal force under the action of in-line wave effect is analyzed.