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The cladding‐structure interaction of precast concrete frame systems under seismic action has not been properly addressed in the past, as shown by several failures occurred under recent earthquakes in Southern Europe, which point out the need of a revision of the current design practice and technology. Dissipative systems of connections are proposed to this purpose within a general framework for seismic design of precast structures with cladding panels. The proposed connection systems consist of friction‐based or plasticity‐based devices interposed in between adjacent cladding panels or between the panels and the resisting frame to control the level of transferred forces and limit the displacements of the structure. Monotonic and cyclic experimental tests are carried out on both single connection devices and structural sub‐assemblies of two panels. Furthermore, cyclic and pseudo‐dynamic tests on a full‐scale prototype of precast structure with cladding panels are performed. The influence on the structural response of silicone sealant is also investigated through experimental testing. The effectiveness of the tested dissipative connections of the cladding panels in enhancing the seismic performance of precast structures is demonstrated by means of nonlinear dynamic analyses considering the influence of the roof diaphragm action. Design guidelines are finally provided for both single connectors and panel structural assemblies based on equilibrium and capacity design criteria.

Despite the long series of European research projects that has led to the setting of fully reliable seismic design criteria for precast structures, recent earthquakes have shown that a weak point still exists in the proportioning of the connection systems of cladding wall panels. Following this finding, this paper outlines an organic setting of the design problem of precast concrete structures including cladding-structure interaction and describes three possible solutions, namely the isostatic, integrated and dissipative systems. The related fastening arrangements, with the use of existing and innovative connection devices, are also described. This paper comments on the results of the pseudo-dynamic and cyclic tests performed at ELSA Laboratory of the European Joint Research Centre of Ispra (Italy) on a full-scale prototype of precast structure. The conception and the experimental performance of the structure with nine different configurations of either vertical or horizontal wall panel claddings are presented. The analysis of the results highlights the effectiveness of the different solutions in a comparative way

The diaphragm action of slab/roof decks ensures the collaboration of different parts of the lateral load resisting system of a building. In reinforced concrete precast buildings for industrial/commercial halls, not seldom the deck is not provided with a cast-in-situ topping: this results into diaphragm action to rely upon the floor mechanical connections alone. In this study, the effectiveness of three different typical floor-beam connections, namely hot-rolled angle brackets, cold-formed angle brackets and dowel bars, on the diaphragm action of the deck has been investigated. To this purpose, simplified macroscopic "behaviour models" have been proposed, based on the results of monotonic and cyclic tests carried out within the framework of the research project Safecast (FP7-SME-2007-2; GA 218417/2009). A numerical model of a dry-assembled precast structure with mechanical floor-to-beam connections has been checked against the results of cyclic and pseudodynamic tests carried out on a full-scale prototype within the framework of the Precast Structures EC8 project (GA G6RD-CT-2002-70002). Non-linear dynamic analyses have then been performed to investigate the diaphragm action effectiveness of the three different technological solutions to connect slab and beams as above considering a seismic action orthogonal to the roof elements. Different stiffness distributions of the lateral load resisting system have been considered, investigating the possible bracing effect induced by an integrated connection system of the external cladding panels. A simplified "design-wise" analytical interpretation of the phenomenon is also formulated and checked against the numerical results.