Rolling into place

On March 26, the Utah Department of Transportation (UDOT) and its contractor, Provo River Constructors (PRC), rolled a newly constructed 354-foot-long Sam White Bridge into place over I-15. The two-span bridge, part of the $1.725 billion Utah County I-15 Corridor Expansion (I-15 CORE) project, was built adjacent to the freeway, and both spans were moved into place simultaneously using Self-Propelled Modular Transporters (SPMT). The bridge construction technique reduced several months of traffic delays and the need for six full freeway closures to a single overnight closure.

The Sam White Bridge, located 30 miles south of Salt Lake City, is one of 63 new, modified or rebuilt bridges in the state-funded I-15 CORE project. The project, which is scheduled for completion by December 2012, also is reconstructing 24 miles of I-15 to add two lanes and extend the HOV lane in both directions, and rebuild and reconfigure 10 freeway interchanges.

The new Sam White Bridge replaces a 1960s-era bridge that was taken down in October 2008 because of height clearance and safety concerns. Off-site construction of the new bridge began in July 2010 in a "bridge farm" adjacent to the freeway, while permanent columns were constructed in the median of I-15 and abutments were built on either side of the freeway. The bridge was constructed on temporary abutments — steel piles that matched the elevation of the permanent columns and abutments.

At 11 p.m. on March 26, approximately 1,000 people gathered to watch as two sets of SPMTs — hydraulic jacks on wheels, controlled by a single joystick — lifted the 354-foot, 3.8 million-pound bridge 21 feet in the air. Then, it rolled 500 feet across eight freeway lanes before being placed onto the permanent support columns. Crews set the bridge into place at approximately 4 a.m. March 27 and reopened the freeway at 7 a.m., three hours ahead of schedule.

The Sam White Bridge will open to traffic this month so work can proceed at another nearby interchange. Six bridges on I-15 CORE were built using the same technique, bringing the total number UDOT has built that way to 25 bridges, nearly double the number moved by all other states combined.

Project: Sam White Bridge
Jurisdiction: Utah County, Utah
Agency: Utah Department of Transportation
Contractors: Provo River Constructors (PRC), a consortium of more than 30 companies
Date completed: July 2011
Cost: Included in the $1.725 billion I-15 CORE project