Seismic Analysis For Substructure Damage Of Long-span Continuous Rigid Frame Bridge

In recent years, with the rapid development of the national infrastructure construction, more and more long span bridges appeared in people’s life, Span continuous rigid frame bridge because of its span, reasonable force, driving comfort,construction and simple in practice has been widely used, while the analysis of the seismic performance of the bridge structure has become a hot spot.Especially when the earthquake happened, a lot of bridges after operations for a period of time, due to environmental corrosion, loading, component aging, degradation of material properties such as the bridge structure have appeared different degree of damage, damage to the structure of the stiffness, bearing capacity, seismic performance and have a great impact,In this paper, based on the above research background is mainly carried out the following work:1 expounds the three basic methods of seismic analysis of bridge structure, the static method, response spectrum method and time history analysis of basic principle and the basic formula.2 The main bridge of Chongqing Qijiang Xintan bridge right bridge as the engineering background,Using Midas/Civil establish the continuous rigid frame bridge finite element model analysis of its dynamic characteristics,Obtained using the response spectrum analysis girders and substructure main control section of the internal forces and displacements.3 The history analysis method of long span continuous rigid frame bridge,considering seismic wave passage effect under the uniform excitation and carries on the contrast analysis shows that: phase difference of the traveling wave effect and consistent excitation structure internal force and displacement difference is bigger,with the phase difference decreases the internal force and displacement of structure tends to uniform excitation.4 Based Resilience skeleton curves of structural damage and restoring force structure intact skeleton curve roughly the same, and the level established under section assumption,Using triple linear skeleton curve was established based on the resilience of the skeleton curve pier substructure concrete cracking.5 Using nonlinear static analysis method, comparative analysis of intact pier and the lower part of the structure of damaged bridge pier 8 degrees in the rare case underthe action of earthquake seismic performance of the structure can be seen: for the rare earthquake, the seismic performance of the structure damage relatively intact structure and its seismic capacity is relatively poor and with pier damage accumulation causes to structure performance point displacement continues to increase.