Effects of Partial-Design-Strength Concrete on the Seismic Performance of Concrete-Filled Tube Columns in Accelerated Bridge Construction

This study evaluated the seismic performance of circular concrete-filled tube (CCFT) columns in accelerated bridge construction (ABC). In these projects, the bridge should be open to service after a couple of days. For this reason, this study evaluated the ability of CCFT columns to perform adequately under gravitational and seismic loading before the concrete reached its design strength at 28 days. A reduced seismic hazard that accounted for this temporal condition was implemented, and a performance evaluation was performed to obtain the CCFT column probability of failure. The performance of a CCFT column was compared with that of a circular reinforced concrete (RC) column of a Caltrans bridge. Probabilistic analyses using reduced seismic loads for the temporary condition indicated that CCFT columns with partial design concrete compressive strength can be used for ABC without resulting in an increased probability of failure. (C) 2016 American Society of Civil Engineers.