Analysis on Seismic Response of Multilayer Steel Frame Structures

The second-order effect on seismic response of the steel frame structure is analyzed with the deflection as the criterion and through considering the geometric nonlinearity or not.Under the condition of changing the flood number and the damping ratio of the structure,the different influence on the seismic response is analyzed based on counting of the value of the top-floor displacement and the displacement between two floors.The result shows that the influence of the second-order effect may not be considered when analyzing the elaslic time history for the frequent earthquake,and it must be considered when analyzing the elastic-plastic time history for the unusual earthquake.Under the condition of the steel frame structure with the same floor number and the different damping ratio, the bigger the damping ratio,the smaller the value of the top-floor displacement,and under the condition of the steel frame structure with the different floor number and the same damping ratio,the higher the floor number of structure,the bigger the value of the top-floor displacement,the greater the seismic response and the more clear the second-order effect.