Efficacia Di Connessioni Meccaniche Tegolo-trave Sull'azione Diaframma Di Strutture Prefabbricate.

he diaphragm effect allows the collaboration of different parts of the lateral load resisting system of a building. If a concrete screed is not poured, as typical for industrial precast structures, such an effect relies on the floor mechanical connec-tions. Starting from the results of local tests on three typical floor-to-beam connections carried out within the framework of the re-search projects Safecast and ReLUIS, simplified macro-models to represent their mechanical behaviour are proposed. A numerical model of a precast structure with mechanical floor-to-beam connections is validated through the comparison against the results of cyclic and pseudo-dynamic tests carried out on a full scale prototype within the framework of the Precast Structures EC8 project. The efficiency of the different technological solution to connect floor and beams on the diaphragm action and on the seismic behav-iour of the structure is then investigated through dynamic non-linear analyses on the bare frame structure and on an externally braced one. A simplified analytical interpretation of the phenomenon is also proposed and validated against the numerical results.