ABSTRACT
To promote Accelerated Bridge Construction using prefabricated components in seismic regions, this paper presents a series of experimental studies on girder-to-bent cap connections and prefabricated pile-pile cap-column system for integral bridge. The girder-to-bent cap connections utilize prestressing strands and continuity diaphragm with dowel bars embedded in to establish superstructure continuity, in which the strands are anchored into the bent cap with two different anchorage details. The prefabricated piles, pile cap, and column are assembled using the sockets preformed on the pile cap. After inserting the precast column and piles into the sockets, the substructure is completed by filling the sockets with grout and self-consolidating concrete, respectively. The large-scale experimental tests were conducted to investigate the seismic performance of the proposed connections and system. The tested girder-to-bent cap connection exhibited excellent seismic performance, and remained essential elastic up to the seismic demands resulting from gravity, horizontal ground acceleration, and 0.5g vertical ground acceleration. Two mechanisms, namely shear friction mechanism and direct tension transfer, were determined to be responsible for ensuring the superstructure continuity under seismic loads. For the pile-pile cap-column system, a plastic hinge was formed in the column in the loading condition representing the extreme seismic loads, while the socket connections remained undamaged throughout the test.
