Based　on　a　simplified　fiber　finite　element　model　(FEM)　of　the　second　unit　of　Ganhaizi　Bridge,　this　paper　presents　the　study　on　the　aseismic　performance,　piers　yield　order　and　internal　force　redistribution　effect　in　plastic　scope.　Compared　with　detailed　FEM,　real　bridge　test　and　shaking　table　test,　the　accuracy　of　simplified　FEM　is　verified.　Take　the　extreme　edge　strain　of　concrete-filled　steel　tubular　(CFST)　columns　as　a　criteria,　the　most　unfavorable　horizontal　seismic　input　direction　is　perpendicular　to　the　bearing　connection　on　both　ends,　and　the　influence　of　vertical　action　should　be　simultaneously　considered.　Results　indicate　that　the　bridge　is　within　elastic　scope　under　design　seismic　ground　motion.　When　turn　into　plastic　stage,　the　main　stress　direction　of　lattice　piers　and　composite　piers　are　both　in　plane,　and　the　axial　forces　increase　less　than　the　seismic　intensity,　while　the　displacements　increase　larger　than　the　seismic　intensity.　Bending　moments　of　composite　high　piers　increase　greater　than　those　of　short　piers,　which　facilitate　the　aseismic　performance　of　the　bridge.　©　2015,　Engineering　Mechanics　Press.　All　right　reserved.