Biaxial Seismic Performance of a Two-Span Concrete Bridge Model with Six ABC Connections

A prerequisite to the implementation of accelerated bridge construction (ABC) in moderate and high seismic regions is reliable data proving that bridges constructed by assembling precast elements can emulate the seismic performance of cast-in-place bridges. Previous seismic studies have not provided sufficient information about the interaction of conventionally reinforced precast concrete elements and connections when they are integrated within a bridge system. This paper addresses this knowledge gap by conducting biaxial shake table tests on a 0.35-scale, two-span bridge model that incorporated 38 precast reinforced and prestressed concrete elements. The elements were joined by using six connection types joining column to footing, column to cap beam, girder to cap beam, deck panels (two types), and deck to girder. The bridge and the connections performed well even under earthquake motions beyond the design-level earthquake and combined large drift ratio demands and substantial in-plane rotation. Although the load path was affected by the interaction among different components, no adverse effect was observed.