Study On Seismic Performance Of Steel Frame Structures With Both Metal Dampers And Viscoelastic Dampers

With the development of social economy and the less and less urban land,the proportion of high-rise buildings in urban buildings is increasing.The frequent occurrence of earthquakes and the popularity of high-rise buildings make people begin to pay attention to the safety of high-rise buildings under earthquake.The anti-seismic technology of high-rise buildings is eagerly to be studied and developed.It is the case that increasing structures' stiffness and strength are the typical ways of traditional anti-seismic methods,which will not only let the layout of the building difficult to design,but also increase considerably in the economy.The energy dissipation technology absorb and dissipate the seismic energy,so that the main strcture will bear a little part of the seismic energy.In comparison of the traditional anti-seismic technology,the energy dissipation technology seems to be more economical,more safe and it is also easier to repair the structure after earthquakes.Therefore the energy dissipation technology develops rapidly.Metal dampers and viscoelastic dampers are widely used as energy dissipation devices.Based on these two kinds of dampers,the seismic performance of the structure is analyzed by time history analysis.The main content of this article is that:1.The basic principle,the components and relative physical quantities of metal dampers and viscoelastic dampers are introduced,which lays the foundation for the application of the algorithm model.2.In this paper,the energy dissipation design method based on equivalent linearization is adopted.The correlation coefficients is obtained when the base shear reduction rate and the displacement reduction rate in the damping curves of the metal damper system and in the viscoelastic damper system is very small.These coefficients are used to design the metal damper system and the viscoelastic damper system,and the distribution of the relative stiffness of the metal damper systemand the viscoelastic damper system is also carried out.3.A 20-story steel frame structure was established as an example to analyze it's seismic response with additional metal dampers or(and)viscoelastic dampers under different operating conditions.At first,this paper set up several basic parameters of the model,and calculate the stiffness of each layers by the Japanese normative method.Then this paper transform the multi-particle system into a single particle system to calculate the target displacement reduction rate of the single particle system.The required stiffness of the single particle system under the action of the BCJ-L2 seismic wave is obtained and the result is assigned to the multi-particle system according to certain principles.Then,the damper configuration method is designed according to the required stiffness of each model And the seismic response of the structure is analyzed by comparing the time history analysis results and the seismic responses of the model.Finally,according to the comparison results and different kinds of targets,the best working conditions are selected.4.The results of time-history analysis show that the inter-layer displacement,the maximum absolute displacement and the shear reduction rate of the model are significantly reduced after the dampers are set up.If a single seismic response is used to be the condition standard,when it comes to the inter-layer displacement,the case 2 is the best;in terms of the maximum absolute displacement,the case 3 and the case 5 is the best,the case 2 is better than any other conditions;in terms of the shear reduction rate,the case 2 is the best;in terms of the energy consumption ratio of the damper,the working conditions have significant energy dissipation effect.If all the seismic responseis used to be the condition standard,then the best case 2 is the best.5.By verifying the relationship between the storage additional component stiffness ratio of the metal damper and the storey ratio and by verifying the relationship between the storage stiffness ratio of the metal damper and the storey ratio,the empirical formulas is obtained.The applicability of the empirical formulas are verified by the 30 storey steel frame structure,the verification results show that the empirical formulas are reasonable.