Antonio Formisano1, Alfredo Massimilla1, Marianna Formisano2 and Gabriele Milani2
1)  Department of Structures for Engineering and Architecture, University of Naples “Federico II”
Piazzale V. Tecchio, 80 – 80125 Naples (Italy)
2)  Department of Architecture, Built Environment and Construction Engineering, Technical University
of Milan, Piazza Leonardo da Vinci, 32 – 20133 Milan (Italy)

Keywords: Historical centres, masonry building aggregates, equivalent frame method, pushover analysis, simplified modelling.

Abstract. Historical centres are often constituted of assemblages of un-engineered masonry building compounds very vulnerable to exceptional actions like earthquakes. Building codes
do not foresee methods to predict their static non-linear behaviour. This paper propose a simplified modelling approach to predict the seismic response of structural units into masonry
building compounds. This approach is based on the Equivalent Frame Method modelling EFM), a technique implemented within a Finite Element Method (FEM) calculation program. The modelling technique has been applied to investigate a simple building compound representative of Southern Italy building aggregates erected during the past decades. Firstly, the whole aggregates have been modelled and analysed in order to evaluate the seismic behaviour of each structural units. Later on, the seismic response of these structural units has been assessed by modelling the single units as isolated structures with boundary conditions applied to consider, in a simplified way, their position in the aggregate and, therefore, the influence of other constructions. Finally, comparison of the achieved results has been carried out in order to confirm the effectiveness of the proposed analyses approach.