Innovative hysteretic device for seismic retrofit of single-story RC precast buildings

In the last decades, many efforts have been made by the scientific community and technicians in order to develop effective and practical retrofit approaches for industrial RC precast buildings. Given the aftermath of recent earthquakes, which identified structural and non-structural dry joints as the highest source of seismic vulnerability, the majority of the retrofit techniques involves interventions at the connections level. The primary function of creating an adequate constraint is nowadays frequently associated to energy dissipation, allowing to both remove the major building weakness and decreasing the seismic demand in terms of elements' stresses and deformations. In the following, a novel metallic hysteretic device intended for beam-to-column connection retrofit is presented. An existing one-story RC precast building with friction beam-to-column joints is considered as case-study structure; mechanical properties of the device are calibrated, and its effectiveness validated though nonlinear dynamic analyses. The proposed device demonstrates its ability in both restrain the relative displacement between structural elements and dissipate an adequate amount of input energy coming from ground motions, preventing structural damage. A comparison with the same device without hysteretic properties, i.e., a non-dissipative device, is also carried out, highlighting the benefits in using the hysteretic version.