Seismic Behavior Of Box Steel Bridge Pier With Built-in Buckling Resistant Steel Plates

The traditional reinforced concrete bridge pier will be damaged and destroyed by earthquake.The steel structure has the advantages of light weight,rapid construction and excellent seismic performance.At the same time,with the continuous improvement of steel structure anti-corrosion,fire prevention and processing technology,the steel structure is widely used in bridge engineering.Therefore,this paper designs a kind of box steel bridge pier structure with replaceable function and anti buckling energy dissipation steel plate.A new type of box steel bridge pier is designed by using high-strength bolts at the root of the pier to connect the replaceable energy consumption area components.The specific structure of the energy consumption area is as follows: a low yield point steel plate is set inside the four wall plates,a common steel plate is set on both sides of the low yield point steel plate,and bolts are used to connect with the wall plates.On the one hand,the built-in low yield point steel plate can restrain the buckling deformation of the wall plate as the anti buckling energy dissipation steel plate;on the other hand,under the earthquake action,the recoverable function of the box steel bridge pier can be realized by replacing the energy dissipation area components.In order to study the aseismic behavior of box steel piers with buckling resistant steel plates under vertical constant load and horizontal reciprocating load on the top of columns,three groups of 7 specimens were designed for pseudo static test.The experimental process,specimen failure mode and test results are analyzed by setting buckling resistant steel plate,axial compression ratio,wall plate strength and eccentric action as influence parameters.The results show that the capacity of the box steel bridge pier specimen is improved after the installation of the buckling resistant steel plate,the buckling deformation of the wall panel is reduced,and the specimen has better seismic performance;compared with the axial compression specimen,the bearing capacity and ductility of the eccentric compression specimen are worse,the positive bearing capacity is greater than the reverse bearing capacity;the axial compression is reduced The results show that the ultimate bearing capacity of the specimens can be reached quickly,and the energy dissipation capacity of the specimens increases with the decrease of the axial compression ratio.Finally,according to the analysis results of the test phenomenon and failure mode,the design optimization suggestions are put forward for the box steel bridge pier with buckling resistant energy dissipation steel plate,and the more accurate simplified formula of relevant design suggestions is put forward,which provides the basis for the application of the box steel bridge pier with this structure in the actual project.