Symmetric in-plane compression of a pantographic lattice structure is modelled and simulated, and the results are compared to previously available experimental data. Said experimental results had shown a peculiar behaviour: depending on the fiber density, the deformed shape could present either one or two swellings under compression. The present article is a preliminary modelling attempt aiming at capturing that behaviour numerically.

This work is an intermediate step towards the extension of a recently proposed block-based model for masonry structures, which was based on a hemivariational approach and inspired from granular micromechanics. Here, contrarily to the previous model, plastic effects will also be taken into account along with damage and elastic behaviours, and the full hemivariational derivation of the strong-form (in)equations will be detailed for the case of a lone vertex spring. The resulting model and methods shall then be used in future works to enrich the behaviours modelled by the previously mentioned masonry model.

Numerical modeling and simulation of architectural heritage has become a topical subject with growing awareness of the importance of protecting and preserving cultural heritage around the world. In this study, a discrete element method (DEM) framework is developed to perform the structural analysis of masonry historical structures. A particular case study is presented for nuraghes, ancient masonry structures located in Sardinia (Italy). The adapted DEM framework is general and particularly suitable for the structural analysis of masonry structures and developed based on a hemivariational formulation to capture complex elasto-damage behavior. In the model, each discrete element is introduced as so-called augmented stone which consists of a rigid stone and surrounding deformable mortar layer. Assuming augmented stones are connected to each other by springs, elasto-damage behavior is modeled introducing suitable deformation and dissipation energy functionals, and the governing equations and damage laws (i.e., Karush–Kuhn–Tucker conditions) are obtained by the hemivariational formulation. An explicit-staggered scheme is adapted to perform the numerical simulations. The applicability of the adapted framework is shown via a case study, tuning simulation parameters and investigating different possible scenarios for nuraghes.