Vulnerability analysis aimed at the safeguard of the Ererouyk basilica in Armenia

The basilica of Ererouyk have recently attracted the attention of the Armenian government, which has decided to promote its preservation by commissioning the National University of Architecture and Construction of Armenia to coordinate a group of Italian and Armenian experts. Built in the sixth century, the three-nave basilica of Ererouyk is unique in Armenia for its size, importance, and typology. For this reason, it has interested many scholars since the late 19th century. In this work, the path followed to know in an accurate way the structural response and to evaluate the vulnerability will be described. The first phase of the study consisted in an in-depth analysis of the damages and restoration interventions that the basilica has undergone during its history. Subsequently, the identification of the material properties both using results of tests performed on the basilica material and referring to literature data was performed. Then the seismic input was defined, following Armenian standards. Aware of the huge uncertainties inherent in the behavior of a sack masonry building that has undergone changes over the centuries, it was decided to perform the structural analysis using methods/models of increasing complexity, from linear kinematic approach to nonlinear time history analyses using three-dimensional finite element model with non-linear properties of the masonry. The systematization of all the information collected has allowed giving a complete and exhaustive picture of the vulnerability of the structure, highlighting the necessity to intervene for the improvement of its structural behavior towards seismic action.