Large-scale experimental validation of a design criterion for damped braced steel structures

The main results of a testing campaign carried out on a large-scale steel frame, seismically improved by the incorporation of bracing members equipped with fluid viscous dampers, are reported herein. This investigation is part of the European Community-funded Research Programme DISPASS, dedicated to the experimental verification of several innovative seismic protection technologies. The tests were performed by the continuous pseudo-dynamic test method implemented at the ELSA Laboratory of the Joint Research Centre – Ispra. This campaign substantially validated a special energy-based design criterion, formulated in previous phases of this research, which was applied to determine the damping properties of the dissipaters installed on the test structure. Moreover, the analytically evaluated capacities of damped braces for mitigating the seismic demand on the examined frame were totally confirmed by the experiments, through a direct comparison with the response obtained in unprotected conditions.