Study On Seismic Vibration Control For Portal Frame Structure With Viscous Dampers

This paper researchs the fluid viscous dampers and its application in the seismic vibration control in the portal frame structure,which is the application study about the technology of energy dissipation and seismic vibration control. Structure energy dissipation and seismic vibration control system refers to making some non-load-bearing elements (for example, support and connecting nodes) designed into energy dissipation bar, or install dampers on some parts of the structure (for example, on connecting nodes).Those energy dissipation bar or dampers keeps in elastic state when there is wind load and small earthquake, and such structure features strong lateral stiffness in order to meet the normal usage. With the increased stress of the structure and increased deformation from the strong earthquake, the energy dissipation rod and the dampers first enter into the state of non-elastic deformation, thus creating a greater damping. Large amount of the seismic energy putting into the structure makes the main structure avoid entering into the obvious non-elastic state and then quickly decrease the effect from the structure, thus making the structure avoid the overall structural damage. Viscous damper device is simple with more economical materials, having a relatively wide range of application. It is still relatively rare to apply it to the portal frame structure and thus is at an initial research phase, but it can provide the necessary assistance for the designers.This paper first describes the related vibration control theory and research of viscous dampers, and clearly put forward the background and content of this research. The seismic vibration control analysis methods selected in this paper belongs to the"Fast Nonlinear Analysis (FNA) " method of partial nonlinear problems, which has higher accuracy and efficiency.To study the damping control of the viscous dampers on the portal frame structure, this paper establishes calculation model using SAP2000 limited analysis software, and then perform the static calculation and modal analysis. Mastering the dynamic response characteristics obtained by the structure cycles and the formation through modal analysis, and then arranges the dampers based on it. Compare the dynamic response characteristics before and after arranging the dampers on the structure by putting into the seismic waves and using time history analysis method. Study and observe the displacement of the control bar node and the shear force and flexural moment of the control component, thus selecting a more reasonable arrangement program, that is, optimizing the location of dampers; Based on the specifications, put other three seismic waves and perform the time history analysis, and then make comparison by outputting time history curves of control components and control node, then study the effect of damping control of viscous dampers on portal frame structure when putting into different spectrum of seismic waves. The results show that seismic vibration control system of viscous dampers has a significant damping effect on single portal frame structure. On the basis of controlling the used number and observing the damping effect, it can be concluded that arranging it on the portal frame structure is the most reasonable position.