Study On Seismic Performance Of Circular Steel Bridge Pier With Partially Concrete Filled

The concrete-filled steel bridge piers attracts more and more attention in engineering field due to its high bearing capacity, the better flexural rigidity, convenient construction and other advantages. Up to now, there are a large number of experimental researches on seismic properties of concrete-filled steel bridge piers, but the experimental researches focus on full packing concrete. There are a few experimental researches on seismic properties of partially concrete-filled steel bridge piers. Based on the investigation of research and application on partially concrete-filled steel bridge piers in China and abroad, the test is conducted about eight partially concrete-filled steel bridge piers under low frequency cyclic load. The parameters include ratio of the concrete-filled height, radius-thickness ratio and slenderness ratio. The hysteretic features,degradation of stiffness, failure mechanism and characteristics are researched. The effects of different parameters are compared.The experimental results showed that partially concrete-filled steel bridge piers with the suitable for filling ratio have the plump hysteretic curve, good deformation ability after the specimens reach ultimate loads. The ductility coefficient are between 3.25and 4.22, the piers can meet the requirement of ductile specimens. The rigidity degradation of columns is low. The specimens have good energy dissipation capacity. The results indicate that partially concrete-filled steel bridge piers with the suitable filling ratio have excellent seismic properties. The filling ratio of partially concrete-filled steel bridge piers are most important, so the optimal range of concrete filled ratio of partially concrete-filled steel bridge piers are brought forward on the basis of the deduced result and experimental data.The substructure pseudo dynamic test used OpenSees software has been study on the method of aseismatic performance for partially concrete-filled steel bridge piers. Experiment shows that the substructure pseudo dynamic test to be better through a particular part of the bridge in tested can get to know the whole bridge structure mechanical characteristics. The substructure pseudo dynamic test with clear concept and loading accurate, can correctly analysis substructure force performance in nonlinear condition.TDAPâ…¢bridge seismic software can simulate the mechanical properties of full-bridge modes under the small earthquakes,the intermediate earthquakes and the sever earthquakes,and the result is good agreement with experimental results.The research fruits can be used to direct the engineering practice of partially concrete-filled steel bridge pie.