The Elasto-plastic Seismic Response Analysis Of BeiJiang Cross-bank Bridge

As a transportation hub, Bridge will cause a serious properties and lives loss when destroyed by earthquake.With the road traffic development of our country , long-span bridges has been developing rapidly in the field of bridge engineering.And large-span continuous rigid frame bridge is one of widely applicatedly bridge models.As China is a country where earthquakes often happens,it is necessary to study the reactions of bridges,especially long-span bridges in earthquake.In this paper, the following tasks are mainly completed under the background of Beijiang cross-bank bridge:(1) The continuous rigid frame bridge seismic theory and finite element method are briefly talked; a bridge Midas model by using the general-purpose finite element program was established to analyze the vibration characteristics of the bridge.(2) Under the bridge, bridge site of the seismic intensity of the regional Department and national norms on the similarities and differences between the vertical seismic input, respectively, a norm elastic response spectrum analysis and dynamic time-history analysis, summarized in the direction of vibration input to the calculation of continuous rigid frame bridge results,bridge,the seismic response analysis for continuous rigid framed bridges considering traveling wave effect is simulated,and compared with the result under the coincident earthquake excitation.(3) Based on the three-line model of rigidity degeneracy the elastic-plasticity character of bridge pier and dowel are simulated, and then the elastic-plasticity dynamic response under the action of large earthquake is analyzed. And so the weak position and precedence of plastic hinge of continuous rigid frame bridge are determined, so as to provide reference for the design of earthquake-resistant.(4) Based on the principle of energy design, the bridge is analyzed by a quasi-static analysis method-Pushover analysis method. The basic principle of the method and its application on large-span continuous rigid frame bridge are introduced. At the same time the influence of higher-order mode and the Pushover analysis results considering dowel-soil interacting and non-considering dowel-soil interacting are discussed in the thesis, so as to provide reference for the design of earthquake-resistant.