Design, Experimental Characterization, and Numerical Assessment of a Resilient Prestressed Lead Damper

The prestressed lead damper (PS-LED) is a novel hysteretic damper that leverages the friction developed between a straight steel shaft and a lead core to dissipate seismic energy. A key feature of the device is the possibility to adjust its axial force by changing the prestress applied to the lead core, enabling customization to meet specific design requirements without changing its physical dimensions, a valuable advantage for serial production. This work presents novel insights in the conceptual design of the device, defining a rigorous framework for the predictive design and deployment of the PS-LED in real-world applications. The accuracy of the design equations in predicting cyclic behavior and the device’s ability to maintain stable performance under repeated cyclic loading are demonstrated in an experimental campaign conducted on two custom-made prototypes. Finally, the retrofit of a case-study structure is designed by using diagonal steel braces equipped with either the PS-LED or a conventional buckling-restrained brace, considered as the state-of-the-art device. The structural performance of the two upgraded buildings is evaluated by comparing the results of time-history analyses, showing the superior energy dissipation capability of the PS-LED compared to the BRB, which determines a consistent reduction of floor accelerations and shear forces acting on the columns of the considered building.