Crumbling of Amatrice clock tower during 2016 Central Italy seismic sequence: Advanced numerical insights

Abstract

The dynamic behaviour and the seismic vulnerability of the ancient civic clock tower of Amatrice, dramatically damaged by the last shocks sequence of 2016 that occurred in Central Italy, is studied in this paper by means of advanced 3D numerical analyses with the Non-Smooth Contact Dynamics Method (NSCD). Thus, a discontinuous approach was used to assess the dynamic properties and the vulnerability of the masonry structure, through large displacements regulated by the Signorini's law, concerning the impenetrability between the rigid bodies, and by the Coulomb's law, regarding the dry-friction model. Afterward, different values were assigned to the friction coefficient of the models and real seismic shocks were then applied in nonlinear analyses. The major purpose of this study is to highlight that relevant data on the real structural behaviour of historical masonry may provided through advanced numerical analyses. The comparison between the results of numerical simulation and survey of the existing crack pattern of the bell tower

Seismic behaviour of rubble masonry: Shake table test and numerical modelling

“…38 Physical and hysteretic damping were implemented, within an implicit time-integration scheme. The non-smooth contact dynamics method was applied to account for masonry fragmentation of monumental constructions, 39 resorting to an implicit integration scheme and to friction alone for energy dissipation. In this section, two modelling approaches are proposed to simulate the dynamic behaviour of the wall both a priori, that is before the tests, and a posteriori, relying on a wealth of information collected during the experiments and on a more detailed description of geometry and boundary conditions.…”

Fragility functions for local failure mechanisms in unreinforced masonry buildings: a typological study in Ferrara, Italy

“…As for nonlinear dynamic analyses, there are several numerical methods that allow to evaluate the structural response employing FEM with different constitutive relationships (e.g., Concrete Damage Plasticity (CDP), Total strain-based crack (TSC)), discontinuous methods (e.g., Non-Smooth Contact Dynamics (NSCD), Discrete Element Method (DEM)) (Clementi et al 2019;Clementi 2021;Ferrante et al 2021) and Discrete Macro-Element Modeling (DMEM) (Chácara et al 2019). One of the better performing approaches appears to be the nonlinear dynamic analysis of the walls considered as rocking rigid blocks.…”

Seismic Vulnerability of Masonry Historical Structures: A Simple Adaptive Nurbs Fe Approach for the Limit and the Subsequent Non-Linear Static Analysis With Few Dofs

“…Discrete element models -or restricting the family of the approaches proposed, Distinct Element Methods DEMs-(as for instance those presented in [36]- [44] without being exhaustive) where masonry is modelled with rigid or elastic blocks and all non-linearity is lumped on joints typically assumed with a cohesive frictional behaviour [43][44]. Such approach is conceived mainly for Non Linear Dynamic Analyses NLDAs [45]- [47] but it can be adapted also to static non linear analyses, or in presence of foundation settlements, albeit requiring typically huge computational efforts. There are obviously other important drawbacks that cannot be summarized in few words in this introduction, but it is interesting to point out how they have recently inspired the implementation of FEM combined with DEM for large scale computations (see for instance [48]- [49]).…”