MPC
Research Finds Concrete Filled Steel Tube Columns Suitable for Accelerated Bridge Construction

Posted: Aug 1, 2019

MPC research at University of Utah indicates that circular concrete filled steel tube (CCFT) columns with partial design concrete compressive strength can be used for accelerated bridge construction because the relatively low decrease in strength is offset by the reduced seismic loads for this temporal condition. As a result, CCFTs are a light-weight lower-cost option for bridge designers who are developing bridges that can be erected and open for use in limited amounts of time.

Having that option is important because columns used for accelerated bridge construction are usually precast components that can be rapidly installed on-site. One of the main challenges with these columns is to keep their weight within a practical range for transporting and handling. Special care is also needed when designing splices to connect the foundation to precast piers in high seismic hazard zones. CCFT columns are an approach that addresses both of these concerns. Because it takes nearly a month for the concrete in CCFT bridge columns to reach their design strength, bridge designers need to know that the columns can perform adequately under gravitational loads and reduced seismic loading before the concrete reaches its design compressive strength.

Luis Ibarra, Ph.D.
University of Utah

Seismic Performance of Circular Concrete Filled Steel Tube Columns for Accelerated Bridge Construction
MPC-19-383