On the reliability of linear elastic analyses of historical masonry buildings: A case study

A finite element model was developed to analyse the Byzantine Basilica of San Vitale in Ravenna (Italy); modelling is intended to help understanding the origin of a diffused crack pattern in the building. In the structural analyses, account was taken of the permanent loads and the seasonal thermal changes. Owing to the complexity of the geometric model, a simplified (linearly elastic, isotropic) constitutive law had to be assumed to keep the computing time within reasonable limits. Accordingly, the adopted constitutive law cannot fully explain the surveyed crack pattern, which is influenced by the brittleness and the anisotropy of the constituent materials; thus, the performed analyses constitute only a first step towards the understanding of the structural behaviour of the Basilica. It is shown, however, that the self-weight alone is largely responsible for the current state of damage in the Basilica. The numerically predicted seasonal change in displacements agree fairly well with the measurements of a monitoring network taken every six months, which proves the reliability of the finite element model.