Seyed Mehdi Zahrai - University of Tehran
Alireza Heisami - Khuzestan University, Ahwaz

Impact dampers are considered among passive control devices. Experimental and analytical research studies have shown that this group of nonlinear dampers has a better performance for reducing structural vibrations as compared to linear vibrating neutralizers. Tall building is a structure that is different from other buildings in design aspects, construction, and operation due to its height. Medium height and tall models are used in the present paper in order to compare the performance of impact dampers in tall buildings. In this study, seismic performance of tall buildings with impact dampers is evaluated by using SAP۲۰۰۰ software. The condition of tall buildings with impact dampers is subsequently introduced. In order to achieve more desirable results for tall buildings subjected to seismic vibration, the earthquake records applied to multi degree of freedom systems are selected from both near and far-field seismic events. This study aims to represent how the impact damper operates in tall buildings and to determine the best location for its installation in order to reduce the response of vibrating system. Using nonlinear time history analysis, structural elements have been investigated based on AISC۳۶۰-۱۰ regulation in the design process. Among the results obtained in this research, reduction in the response of multi-degree-of-freedom systems in vibration condition using impact damper placed on the top floor can be mentioned. Moreover, it was observed that the more the frame height and its number of spans, the better the effect of placing impact damper in a story close to the roof as compared to placing itin the middle stories, which is due to the combination of vibration modes.

Nonlinear damper, Impact damper, Tall Building, Near and far-field earthquakes, Numerical analysis