Experimental investigation of the response of precast concrete cladding panels with integrated connections under monotonic and cyclic loading

One major issue in the design of precast structures against earthquakes is the importance of cladding connections on the overall response. In the present work, an experimental investigation on the monotonic and cyclic behaviour of fixed panel connections, also referred as 'integrated' connections, is reported. The extensive experimental program was performed at the Laboratory for Earthquake Engineering of the National Technical University of Athens, Greece, within the framework of the FP7 European project SAFECLADDING, and aimed at the investigation of the behaviour of several types of connections materialized with vertical reinforcement bars, referred as 'rebar' connections, or steel mechanisms of two types: 'wall shoe' and 'steel plate'. The results show that rebar and wall shoe connections can attain large ductility and strength, but with significant pinching for large lateral displacements, due to the plastic deformation of the connections' rods that can lead even to residual joint opening. When this happens, apart from the horizontal slip that can occur, the energy dissipated decreases, as evident from the corresponding normalized energy dissipation capacity curves of the tested specimens. The damage to the panels observed during the tests was generally limited, except of large drifts combined with strong connections, and the overall failure was determined by the failure of the connectors.