Seismic vulnerability assessment of existing masonry buildings. A comparison between two different modeling approaches

Seismic vulnerability assessment of existing masonry buildings requires to implement numeri-cal models that are both reliable and computationally efficient. To date various modeling ap-proaches have been proposed in literature in order to evaluate the global response of such structures within a Finite Element Model (FEM) approach, such as the Equivalent Frame Model (EFM) and the Continuum Model (CM). The first is based on a simplified scheme comprising a system of mono-dimensional non-linear frame elements (such as piers and spandrels), by obtaining a significant structure simplification with an important reduction of the computational costs. Whereas, the second approach involves to model the structure through two- or three-dimensional continuum finite elements (as shell or solid). In this way a more refined model is obtained, even if the computational burden is drastically incremented and a large amount of data is required, too. The paper presents a comparison between the two modeling approaches described above, used to implement and to analyze a case study, an existing masonry building located in Italy being irregular both in plan, since it is L-shaped, and in the elevation. Non-linear pushover static analyses are performed, and comparisons among the obtained results by means of both the models considered are shown and commented.