Seismic behavior analysis of large-span steel structure of the National Stadium under severe earthquake

Study of seismic behavior of large-span steel structure of the National Stadium was performed by dynamic elasto-plastic analysis method and static elasto-plastic analysis and capacity spectrum method under severe earthquake excitation.Elements with concentrated plastic hinge were adopted for the analytical model.The input motion for the dynamic elasto-plastic analyses included 4 earthquake records and 1 artificial wave.Static elasto-plastic analyses included 12 loading cases.Results of both dynamic analysis method and capacity spectrum method indicate that under severe earthquake the maximum displacement is much less than the limit value,few members of the main structure yield slightly,a few plastic hinges are formed in the secondary structural members and the load-carrying capacity of few of them is lost,but the stiffness and the load-carrying capacity of the structure is not decreased.The analytical results indicate that the design of the steel structure of the National Stadium achieves the earthquake performance objectives.Loading pattern of pushover analysis is discussed by evaluating dynamic analysis results and static analysis results,which may be a reference for future seismic behavior study of large span steel structures.