Study On Seismic Behavior And Design Method Of Replaceable-on-site Steel Bridge Pier

An innovative replaceable-on-site steel bridge pier(RSS)with replaceable steel slit dampers has been developed to meet the needs of rapid restoration of performance and functionality of bridge structures after earthquakes.The damage elements of the RSS can be controlled and easily replaced once the damage occurs during the earthquake.The steel slit damper in RSS bridge pier is introduced to provide the flexural capacity,while dissipating the seismic energy through shear deformation and keeping the bridge pier elastic under horizontal loading.The FEM model of the RSS was constructed with ABAQUS under monotonic and cyclic load to investigate the influence of axial compression ratio,effective slenderness ratio and damper strength on the failure modes,hysteretic curves and skeleton curves of specimens.The results indicate that:(1)The RSS bridge pier with properly design is failed by the plastic deformation concentrated on the replaceable dampers while the other components remain almost elastic,hence the RSS bridge pier can be easily repaired after an earthquake;(2)The RSS bridge pier showed stable hysteresis behavior and no deterioration in bearing capacity is observed even in large drift;(3)The ultimate lateral load of RSS bridge pier increased with the increase of axial compression ratio;(4)The lateral load almost linearly increased as the damper strength increased.(5)As the slenderness ratio increased,the lateral strength decreased but no deterioration in bearing capacity even in large slenderness ratio.Based on the finite element analysis results,the load bearing mechanism was further analyzed,and a formula is suggested to calculate the flexural bearing capacity of RSS,which shows good agreement with the FEM results.This paper can provided reference for the engineering practice and study of sustainable development of bridge engineering.