Experimental Analysis on the Cyclic Performance of Bolted Precast Connections

The cyclic performance of the connections between precast elements affects the seismic behavior of the whole structure considerably. Particular attention is needed for column-to-foundation connections, which have to guarantee the capacity of the structure to withstand both vertical and horizontal loads without collapsing during a seismic event. A series of full scale precast column-foundation sub-assemblies have been tested aiming to define the performance of bolted joints made by column shoes and anchor bolts. Tests were carried out by imposing cyclic displacements of increasing amplitude and by applying constant vertical load. Such performance was compared to that of cast-in-place columns in terms of ductility, energy dissipation, stiffness and strength degradation. The results of the research showed that the cyclic behavior of properly designed bolted joints is equivalent to that of cast-in-place connections, which allows to consider those as energy dissipative according to current design Codes.