To investigate the longitudinal seismic system of long-span and super-long continuous bridge across the sea,a continuous girder bridge with span arrangement(60+22×80+60)m was cited as an example and the seismic design of the bridge was carried out,respectively using the conventional seismic system and the seismic mitigation and isolation system.The software Midas/Civil was used to set up the finite element model for the overall bridge model.And the responses of the piers of the bridge using different seismic systems with different boundary parameters under the action of the rare earthquake were compared.The results show that when the conventional seismic system is used on the bridge with multiple fixed piers,it can reduce the internal force response of the piers and limit the longitudinal displacement of the bridge to a certain extent,but the internal forces and displacement of the bridge are still at a high level.Therefore,conventional seismic system is not an effective seismic system.For the ductility seismic system,the energy dissipation effect of plastic hinge can effectively reduce the internal force response of piers,and its plastic deformation effect will increase the longitudinal displacement of the bridge.However,for bridge piers located in water,due to the difficulty of repairing components after earthquakes,more attention should be paid when considering the use of a ductile design system.When the seismic mitigation and isolation system is used on the bridge,friction pendulum bearings can effectively reduce the internal forces of piers and limit the longitudinal displacement of the bridge which have excellent effect of seismic isolation.Friction pendulum bearings also significantly improve the safety of the bridge.The relationship between the response internal force and displacement of the bridge and the number of isolation bearings do not obey linear relationship,which should be determined after detailed calculation.
关键词
大跨超长联/抗震体系/传统设计/减隔震设计/延性设计/抗震性能/连续梁桥
Key words
long-span and super-long unit/seismic system/conventional seismic system/seismic mitigation and isolation system/ductility seismic system/seismic performance/continuous bridge
维普
万方数据