Discontinuous vs continuous approaches for the nonlinear dynamics of an historic masonry tower

The present paper investigates, from an advanced numerical point of view, the progressive damage of the Amatrice (Rieti, Italy) civic clock tower, after a long sequence of strong earthquakes that struck Central Italy in 2016. Two advanced numerical models are here used to provide an insight into the modalities of progressive damage and the behaviour of the structure under strong dynamic excitations, namely a Discrete Element Method (DEM), the Non-Smooth Contact Dynamics (NSCD) method, and a FE Concrete Damage Plasticity (CDP) model. In both cases, a full 3D detailed discretization is adopted. From the numerical results, the role played by both the actual geometries and the insufficient resistance of the constituent materials are envisaged, showing a good match with actual crack patterns observed after the seismic sequence.