The Basilica of San Vitale in Ravenna: Investigation on the current structural faults and their mid-term evolution

A finite element model was developed to analyze the Basilica of San Vitale in Ravenna (Italy), a Byzantine building which suffers diffused cracking and excessive deformation, mainly as a consequence of complex architectural vicissitudes (extensions, demolitions …) and ground settlements. In the structural analyses, account was taken of permanent loads (self-weight), boundary displacements increasing in time, and seasonal thermal changes. Thanks to previous topographical surveys of part of the building, to chemical and mechanical investigations, the geometry of the Basilica and the main physical properties of the materials are reasonably well defined. The geometric model does not virtually neglect any structural element and accounts for the lack of symmetries in the building. Because of 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 performed analyses constitute only a first step toward the understanding of the structural behavior of the Basilica, as the adopted constitutive law can only partially explain the surveyed crack pattern, which is influenced by the brittleness and the anisotropy of the constituent materials.