Dissipative tie-rods restraining one-sided rocking masonry walls: analytical formulation and experimental tests

This paper presents the analytical formulation to investigate the seismic performance of rocking masonry walls restrained by Dissipative Tie-rods (DTs). Experimental tests on one-sided rocking walls restrained by a DT are used to validate the formulation based on the dynamics of a two-degree-of-freedom rigid-block rocking on a rigid foundation, and to calibrate the mechanical parameters entering the equations of motion. The dynamics of the rocking wall restrained by DTs is fully described by separately considering each contribution due to self-weight, metal tie-rods, fluid viscous dampers, recentering components. The framework is then applied to the main façade of a monumental building, a church damaged by the recent 2023 Turkey earthquake. The numerical analysis considering that earthquake confirmed the expected benefits offered by the DTs: reduction of the peak response at least by 60% (in comparison with the case of façade restrained by a traditional tie-rod), a reduction of the vibration time by almost 60%, avoidance of tie-rod yielding or failure, reduced punching effect against transverse walls and efficient energy dissipation (around 1/3 of the total input energy).