Seismic Performance Analysis On The Segmental Concrete Filled Steel Tube Piers With Replaceable Energy Dissipation Devices

The precast segmental bridge pier has great economic significance and social value,such as high construction efficiency,little interference to existing traffic and environment,strong post-earthquake recovery ability,and so on,which has been widely concerned by engineering and academic circles.However,there is no systematic and definitive solution to the problems of concentrated damage and insufficient energy dissipation capacity of the piers under earthquake,which is an important reason why they have not been widely applied in moderate and strong seismicity areas.In order to improve the performance of precast concrete filled steel tube piers in earthquake area and reduce the damage and repair cost of piers after earthquake,the segmental concrete filled steel tube piers with replaceable energy dissipation devices were proposed in this paper,and the following research work has been carried out:(1)This paper summarized the application of the precast segmental bridge piers in bridge structures at home and abroad,as well as the related research work on seismic performance.Combined with the new concept of integrating ductile seismic into the precast segmental bridge piers at present,the purpose and content of this paper were put forward.(2)The quasi-static loading test scheme of the segmental CFST piers with replaceable energy consumption device were designed and proposed.The preliminary preparation work of material selection,fabrication and assembly of test pieces was carried out according to the current specifications,and then the quasi-static loading test was carried out successively for the test pieces.(3)This paper analyzed the test phenomena and test results of the segmental CFST piers without energy dissipation devices,with replaceable energy dissipation devices and repairing it.The seismic performance of the segmental CFST piers was evaluated through the comparison of hysteretic performance,lateral strength,cumulative energy consumption,self-centering ability,stiffness degradation and damage deformation,so as to explore the feasibility of new structure type bridge piers.(4)Based on the ABAQUS platform,the entity models of the precast segmental test piers were established by using the refined finite element numerical analysis method.Through the comparative analysis with the test results,the reliability of the simulation method to deal with the geometric,contact and material nonlinear problems of piers was verified.(5)Taking the section contribution rate of energy dissipation devices,the arrangement along the pier height,the slenderness ratio and yield strength of energy dissipation steel bars as the research parameters,the parameter sensitivity analysis of 26 segmental CFST pier models with energy dissipation devices was carried out.The influence of the main control parameters of energy dissipation devices on the seismic performance of the new pier was studied,and reasonable suggestions were given.