The Seismic Performance Test And Numerical Analysis Of Bridge Piers With Different Systems

Prefabricated piers have the advantages of environmental protection and high construction speed compared with cast-in-place piers.However,the lacking in seismic performance of prefabricated piers limits the application of these piers in moderate and strong earthquake area.Scholars have proposed various solutions to improve the seismic performance of fabricated piers by combining various types of components,using new materials,and adding energy-consuming devices.However,these solutions are complex in structure and mechanics,and they are more difficult in design and construction.Therefore,this paper proposes the semi-prefabricated piers with simple connection and easy construction.To investigate the seismic performance of semi-fabricated piers,the pseudo-static tests of 3 columns with different structural forms(cast-in-place,semi-prefabricated,prefabricated)and non-linear numerical simulations have been done.and the design parameters of piers were optimized.Several main contents have been done in this study as follows:(1)Firstly,based on the pseudo-static tests of three pier specimens,hysteresis behavior and energy consumption capacity are investigated,and the test results were compared and analyzed.(2)Secondly,according to the three pier specimens,the nonlinear finite element models considering the bond-slip effect and nonlinear behavior at the joints were established.The numerical results were compared with the experimental results to verify the accuracy of the finite element models.The influences of the axial load ratio,the ratio of the longitudinal reinforcement of the bottom segment,and the height of the bottom segment on the seismic performance of the semi-prefabricated pier were analyzed.(3).Finally,based on the analysis of the displacement components of the bridge pier tops and the coupled analysis of parameters,the appropriate height of the bottom section of the pier was calculated.The research show that,the seismic performance of semi-prefabricated piers is better than that of prefabricated piers;the numerical simulation results of bridge piers based on fiber model are basically consistent with the results of pseudo-static tests.Higher axial pressure ratio,higher bottom segment lead to high energy consumption within a certain range.The effect of bottom reinforcement ratio on the energy dissipation capacity of semi-prefabricated piers varies with the axial load ratio and the height of the bottom segment.Different axial load ratios and bottom segment reinforcement ratios correspond to different appropriate heights of the bottom segment.Appropriate heights of the bottom segment can significantly improve the seismic performance of piers.