| Bridge engineering plays an important role in the whole traffic network,seismic design is obviously important for bridge engineering.Bridge pier is an important component of the bridge structure,especially for the pier rigid bridge structure,compared with the seismic isolation bearings can be used in the bridge,the seismic performance of the pier column plays the key role in the bridge structure,bridge pier ductility is the only defense of the whole bridge structure anti earthquake.The plastic deformation capacity and energy dissipation capacity of the bridge pier is decided whether it can achieve the expected seismic design goal.Low piers exist widely in the bridge structure,and low pier under the weight of the superstructure is huge and meet the load combination of pier section stress.The designs of section size of pier need larger,resulting larger stiffness and poorer deformation ability.Seismic ductility design of low pier has become a thorny problem of bridge design.In this paper,aiming at the low piers,based on the seismic design philosophy of passively split pier,and the open platform OpenSees,the seismic performance of the passively split pier under seismic loading are further research.The main research contents of this paper are as follows:(1)The passively split pier was analyzed in theory.The passively split pier which pier is consolidation was analyzed its ductility.Calculation the increment of displacement of the passively split pier caused by stress mechanism and the curvature of the pier,obtain the calculation formula of the ductility of split piers.Discussed the influence of shear connectors to initial passively split pier stiffness,confirm the passively split pier calculation formula of initial lateral stiffness.(2)Discussed the finite element analysis method to study the passively split pier.Established the finite element model of the passive split piers,and the correctness of the passively split pier,prove the passively split pier nonlinear finite element model is correct.(3)Established finite element models of passively split pier with different slot structure.The introduction of the concept of width ratio,adjust the width ratio means that adjustment the cross-section of shear connector height,the influence of the height of the shear connectors was significantly greater than the impact of shear connector in the width of the passively split pier,research seismic performance of passively split pier affected of the width ratio change.(4)Established finite element models of passively split pier with different shear connector structure.In the same condition of stiffness ratio,study the seismic performance of the passively split pier was influence of shear connector number.The above research results,provides the passively split pier seismic theory,in-dqpth study on the shear connectors which is one of the important components of the passively split pier,provides the design basis for the seismic design of passively split pier,and puts forward the design proposal of passively split pier. |
