Seismic Vibration Control for Portal Frame with Viscous Dampers

In order to study seismic vibration control for a portal frame structure with viscous dampers,SAP2000 software in finite element method is used to establish the analysis model and to make mode analysis. According to its period and formation, the dynamic characteristics of the structure are mastered, then viscous dampers could be set up. By inputting EL-centro three-wave, different dynamic response of the structure between pre and post using viscous dampers is compared. Through observation and study on the displacement of control joint and axial force of control member and the vertical displacement of control joint, reasonable setting manner is selected. According to standards, another three waves are inputted to do time history analysis and to compare the time history curve of control member and joint. Then, damping effect of the structure is studied by inputting different spectrum characteristics seismic wave. It is proved by numerical results that optimal location of viscous dampers is on the roof of the structure, on the basis of controlling its number.