Verification of damped cable system performance in the seismic rehabilitation of buildings

The performance capacities of the damped cable system are evaluated by the results of an experimental campaign developed on a full-scale three-story rein-forced concrete structure retrofitted by this innovative protective technology. The experimental activity, carried out as part of a European Community funded Research Project, consisted in repeated series of forced vibration tests, which of-fered a first realistic verification of the system response capabilities. This pro-vided essential information on the on-site behaviour of the assembled system components, among which cable connections with fluid viscous spring-dampers and story beams. The dynamic test results, elaborated in terms of equivalent transmissibility coefficients, energy dissipated by the spring-dampers and the en-tire structure, relevant energy ratios, and equivalent viscous damping coefficients, showed a significant improvement of structural performance in rehabilitated conditions, as well as a satisfactory correlation with design predictions. The analytical model of the structure, properly calibrated on the experimental data, was also used for a numerical seismic investigation, which confirmed the high degree of protection guaranteed by the examined technol-ogy.