Application of Eddy Current Energy Dissipation Systems in Seismic Isolation
摘要
For their economy, effectiveness, and simplicity in design, Base Isolation Systems (BISS) have become the most widely applied systems for seismic protection of structures. Nowadays, countries like Japan have at least 4,500 buildings protected by these systems. To improve their performance, BISS incorporates energy dissipation systems, ranging from lead cores to friction surfaces. This research work examines the performance of an innovative energy dissipation system, consisting of conductive plates and magnetic fields that induce eddy currents (EC). In the context of experimental tests involving free vibration and seismic excitation, the mechanical behavior of a roller isolation bearing system coupled with the EC system is characterized. The vibration periods of the roller bearing as well as the isolation system were determined. Additionally, numerical simulations were conducted to establish the magnitude of the force generated by the EC dissipation system. Finally, some conclusions are presented regarding the effectiveness of the proposed dissipation system and the possibilities of its implementation in full-scale structures. The rolling support seismic isolator coupled with a damping system achieves a reduction of seismic acceleration by up to 85% in the analyzed events, based on the records of the Northridge and El Centro earthquakes.