A discrete element method is proposed to investigate the structural behavior of
ancient stone masonry heritage. The computational model is based on a
hemivariational approach that enables the simulation of complex elasto-damage
behavior and collapse mechanisms. Each discrete element is defined as an
augmented stone, consisting of a rigid block with an equivalent interaction
layer, with interactions modeled through springs governed by energy-based
damage laws. The governing equations and damage criteria are derived by a
hemivariational principle, while an explicit-staggered integration scheme is employed
to simulate the evolution of deformation, cracking, and progressive collapse. The
proposed methodology is particularly suited to address the challenges of
historical stone masonry, which is often characterized by irregular geometry,
material heterogeneity, and long-term degradation. By combining physical
modeling with numerical simulation, the framework provides insight into
both global stability and localized damage phenomena that are essential to
understanding structural vulnerability. To demonstrate its applicability, the
framework is applied to the real case of Nuraghe Palmavera, a Bronze Age
masonry monument of great archaeological and cultural significance in Sardinia
(Italy). The results reproduce overall stability features as well as possible
localized damage patterns, thereby validating the ability of the discrete element
approach to capture realistic structural behavior. Beyond methodological
advances, this study highlights the role of physics-based simulations in the
preservation of architectural heritage, offering valuable support for conservation
planning, risk assessment, and the long-term safeguarding of vulnerable masonry
monuments.
Keywords
discrete element method, stone masonry structure, cultural
heritage, variational principle