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A new system for the seismic retrofit of R/C frames has been tested within an extensive experimental investigation on shaking table, carried out for the TREMA project (Technologies for the Reduction of seismic Effects on Architectural Manufacts)[1]. The 3D model was a ¼ scaled frame, with three stories, two and one bay in the two directions respectively, originally designed for gravity loads only [1]. It was previously tested, firs with base isolation and then in the fixed base configuration, up to being severely damaged. After repairing, by just restoring concrete in broken joints at the 2nd floor with high strength mortar and injecting large cracks with epoxy resin, the model was upgraded with the DIS-CAM system. This system is an improvement of the CAM system described in [2]. The original CAM system provides confinement to columns using steel angles and steel ribbons, while the new improvement is based on the addition of special steel connecting energy dissipating elements at the beam-column joints. The retrofit determines an increase of strength and ductility of single elements and joints, as well as an increase of the overall ductility, if it is designed according to the capacity design criterion forcing the structure to develop a strong column-weak beam mechanism.

The experimental tests were carried out with the two simultaneous horizontal components of the Umbria-Marche 1997 earthquake, up to 0.52 g normalised peak value of the acceleration (NPA as defined in [1]) of the table and with the three simultaneous components of the near-fault Northridge Rinaldi record, up to 0.84 g horizontal NPA. The confinement of concrete, the strength …