Experimental investigation of the cyclic response of reinforced precast concrete framed structures

Abstract

This paper summarizes the results of an experimen- tal program devoted to assessing the main structural characteristics and criticalities in the seismic response of typical reinforced precast concrete structures in Italy that were severely damaged by major earthquakes in May 2012. Two 3⁄4 scale two-bay, three-story precast concrete frames with and without cladding panels were subjected to a quasi-static cyclic top displacement his- tory consisting of symmetric stepwise increasing drift cycles. Pinned beam-column connections consisted of neoprene pads with vertical steel dowels working in shear. The flexibility of the cantilevered static scheme forced large displacement demand and incompatible transfer of the horizontal forces to occur in joints lack- ing shear and ductility capacity. In addition, displace- ment incompatibility between structural elements and cladding panels caused the premature failure of their connections. The results demonstrate the inadequate performance of this structural solution because of its beam-to-column and panel-to-structure connection systems, the responses of which reaffirm that this frame typology should not be used in areas of high seismic hazard because of its nearly elastic-fragile behavior.