In the years after World War II, but also more recently, the cases of replacement of individual parts of masonry by reinforced concrete elements were numerous, influencing the overall static and dynamic behavior of the buildings.
The most interesting example concerns the frequent replacement of the old, and often destroyed, wooden trusses with similar elements in reinforced concrete. In this way, the original structure was completely unnatural and the new one was not capable of fully exploitsexploiting the possibilities offered by the concrete material. Apart from this intervention type, it followed a greater involvement in the use of the reinforced concrete due to the significant increase of the vertical loads on the outside walls.
Such interventions, already heavily invasive infrom both the historical and aesthetic point of view, resulted posed numerous problems of technical-structural types, such as the increase in the loads (and the consequent seismic action), stiffness, and shear strength inadequacy for some elements.
The application of reinforced cement coating (jacket) on one or both sides of the wall was massively used to improve the lateral resistance and energy dissipation capacity of the structural component. This method was very easy to apply and, at the same time, had good efficiency. For these reasons, it was widely used to strengthen masonry walls in different countries all over the world.

Hence, the walls were covered by concrete slabs, with rigid concrete floors and a massive concrete curb on the top of the perimeter walls. In this way, it was possible to calculate the structure with the well knownwell-known POR method proposed by Tomazevic.

In short, the attempt was trying to make reality look like the analytical model, thereby reversing the structural restoration priority that has to make the analytical model look like reality, even if it is not easily be outlined.