Large-Scale Biaxial Shake-Table Studies of a Precast Bridge Model

Abstract

Shake-table studies were conducted on a large-scale, two-span accelerated bridge construction (ABC) bridge model that incorporated 38 precast concrete elements and six emulative ABC connection types. The studies were aimed to assess the seismic performance of the bridge model and the six ABC connections under biaxial horizontal ground motions simulated at the Earthquake Engineering Laboratory at the University of Nevada, Reno. The bridge model was subjected to successive earthquake motions ranging from 20% to 200% of the design earthquake motion. Test results showed that the ABC bridge model matched the target performance of cast-in-place (CIP) bridges by limiting plastic hinging to columns and maintaining other components as damage-free. The ABC connections maintained the structural integrity of the system even under drift ratio demands on the columns higher than 7.5% combined with substantial in-plane rotation (e.g., larger than 0.008 rad) of the superstructure.