Low-Damage Precast Columns for Accelerated Bridge Construction in High Seismic Zones

Accelerated bridge construction (ABC) is a feature incorporating new technologies, advanced planning, and new detailing to expedite bridge construction. Accelerated bridge construction offers many benefits, the most important of which is faster onsite construction. Precast systems and members are the key components of ABC. Even though the application of precast systems is common in low and moderate seismic regions, implementation of precast columns in high seismic zones has been scarce because of uncertainty in the seismic performance of precast member connections. Three low-damage materials, ultrahigh-performance concrete (UHPC), engineered cementitious composite (ECC), and nickel-titanium shape memory alloy (NiTi SMA), were incorporated in this study, in either the connection or the plastic hinge of a half-scale bridge column test model to develop a precast column that exhibits improved seismic performance over columns built cast-in-place with conventional materials. The column damage was significantly lower than in a reference cast-in-place column (CIP) in which the precast column damage was limited to only ECC cover spalling after 12% drift-ratio cycles. The precast column average residual displacement was 79% lower than that in the CIP, ensuring postearthquake functionality of bridges built with the proposed system. A UHPC-filled duct connection used in the column-to-footing connection showed no damage even after 12% drift-ratio cycles. A simple finite-element model was developed to simulate the column test responses. Good correlation between the measured and calculated local and global responses was achieved.