On the use of cold-formed thin walled members for vertical addition of existing masonry buildings

According to the current trend for sustainable constructions in urban area, in this paper different constructive technologies for vertical addition of existing masonry buildings have been examined. Based on the analysis methodology of the new technical Italian code (M. D. 14/01/08) for assessing the behaviour of historical masonry buildings, a FEM model of a structural masonry unit has been implemented in order to allow for the comparison among different solutions for vertical addition, namely traditional technologies and innovative ones. A numerical campaign of linear dynamic analyses has been undertaken by changing both the number of floors (1, 2 and 3) and the strength (fk=1, 3 and 6 MPa) of the base masonry structure. The seismic performance of the analysed structures, expressed in terms of PGA, has shown that cold-formed steel systems represent the best solution for vertical addition of existing masonry buildings.