Development, design and experimental validation of a steel self-centering device (SSCD) for seismic protection of buildings

The paper describes the development of an original steel self-centering device (SSCD) for improving the level of seismic protection of new and pre-existing structures. In particular, the proposed hysteretic device exhibits two technical features essential to protecting structures against the effects of an earthquake: re-centering and recovery of the structure's original dissipative resources (Dissipative Elements) after a seismic event. The overall mechanical behavior of the hysteretic device was first defined in terms of its main internal components. A refined parametric analysis was then conducted by varying the mechanical properties of the steel elements responsible for seismic energy dissipation; this allowed optimizing the retrofitting/protection capacities of the system. To this end, various grades of steel, used not only in traditional structural engineering applications, but also in automotive engineering and packaging, were selected, and specimens of each subjected to experimental monotonic and cyclic tests to determine the most suitable for our purposes. A full-scale prototype SSCD was finally fabricated and checked through cyclic tests to evaluate its mechanical and dissipative performance.