Modal pushover analysis of an irregular continuous bridge

Based on basic concept of modal pushover analysis(MPA),details of estimating an irregular continuous bridge's seismic displacement demand with MPA were investigated.Position selection of bridge's displacement monitoring points capacity spectrum form,inelastic demand spectrum's building and modal combination rules were analyzed with a MPA procedure for an irregular continuous bridge.The lateral seismic displacement demands of four irregular continuous bridges were estimated with the MPA procedure and compared with the rigorous inelastic time-history analysis.Results show that although the irregular continuous bridges mian modes have interactions after their piers yield,the MPA procedure can estimate reasonable seismic displacement demand.