The effect of the side bearing resistant system of the rocking brace - viscous damper on the performance of shear frames

Document Type : Research Article

Author

Faculty member, Department of Basic Sciences and Engineering, Faculty of Science and Technology and Organizational Resources, Amin university, Tehran, Iran

Abstract

According to the experiences gained from past earthquakes, the need for a structure that has less damage and can be easily repaired after an earthquake is essential. One of the methods of depreciating seismic energy and having a repairable structure is to use the rocking brace system. In this study, the effect of using swing brace along with liquid viscous damper in improving the seismic fragility of structures has been investigated. The swing brace is formed by adding a liquid viscous damper. The set of this system has been installed at the base of the structure. For numerical studies, a three-story shear structural model with nonlinear behavior is considered. The examined structures in an uncontrolled state and equipped with a brace-swing-damper system have been subjected to the vibration of 60 earthquake records recommended in the seismic regulations with different specifications and frequency content. The results of dynamic analyzes are subjected to regression analysis to obtain the relationship between the intensity of earthquake excitation and the response of the structure and to estimate the seismic demand of the structure. Finally, the fragility curves for mild, mild, extensive, and complete performance levels for three performance criteria including drift ratio of structural members, drift ratio of non-structural members sensitive to drift and acceleration of non-structural members sensitive to acceleration have been determined and compared. The results indicate the effective performance of the brace-swing-damper system in improving the seismic fragility of the studied structures, so that the fragility has decreased by 35%.

Keywords

Main Subjects