Theoretical analysis and experimental validation of multi-level friction damping system

Most traditional passive friction dampers are limited to the design of single activated energy dissipation mechanism; therefore, when the seismic intensity is not strong enough to activate the mechanism, traditional friction dampers can only increase stiffness of the structure just like braces; only when the mechanism is activated will the energy dissipation elements perform energy absorption and assist the structure to absorb received seismic energy. The objective of this study is to improve this defect of traditional friction dampers, developing a Multi–Level Friction Damper (MFD) with a two-stage energy dissipation mechanism, helping building structures (e.g., hospitals, high-tech plants) reduce the acceleration responses of the superstructure. MFDs are proven to provide more comprehensive protection and have higher energy dissipation benefits than traditional friction dampers by the validation of numerical analysis and shaking table test. The study in turn performed parameter fitting with the results of the numerical simulation analysis and shaking table test, and the experimental results turned out to be satisfactory, validating the accuracy of the theoretical formulas.