Seismic response of MRF-CBF dual systems equipped with low damage friction connections

The work herein presented proposes an innovative approach to the use of friction dampers in seismic resistant steel structures. In fact, reference is made to dual systems where dissipative devices are located at beam ends, column bases and intersections of chevron braces. Friction devices are those investigated in the framework of the European Research Project “FREEDAM” (FREE from DAMage steel connections), supported by Research Found for Coal and Steel (RFCS). The aim of this project is the development of beam-to-column connections equipped with friction dampers showing low damage. Investigations concerning the prototype structure herein presented have been carried out to gain relevant information in the framework of the research project. Incremental Dynamic Analyses (IDA) are developed with reference to the maximum interstorey drift ratio, the maximum slippage velocity and the cumulative displacement, i.e. the travelled distance of the friction dampers. Moreover, the influence of the seismic intensity measure on the required friction damper stroke is investigated.