APPLICATION OF MAGNETO-RHEOLOGICAL DAMPERS IN CONCENTRICALLY BRACED FRAMES

The ongoing research project SEMNAL-MRD (Seismic protection of engineering structures through dissipative braces of nano-micro magneto-rheological fluid dampers), aims to develop a seismic protection system employing a semi-active structural control system. The most promising devices appear to be magneto-rheological (MR) dampers. The current paper describes the typology and working principle of MR dampers. Furthermore, the innovative solution for the current MR damper of composite nano-micro MR fluid of passive/semi-active control is presented in terms of technical solution and principle scheme. The experimental and numerical investigation program developed for the characterization of the MR damper prototype of 10tf capacity developed in the project is presented. With regard to the numerical investigation program, a case study is presented which addresses the application of MR dampers in concentrically braced frames. In particular, the numerical modelling of a hybrid system composed by a buckling restrained brace (BRB) and a MR damper is presented. The main conclusions and future research activities are finally presented.