Dive Brief:

• The Oklahoma Department of Transportation (ODOT) has re-opened a portion of Interstate 235 in Oklahoma City after installing two spans of a 45-foot-tall, 4-million pound prefabricated railroad truss bridge built offsite, according to Oklahoma News 4.
• This is the first time ODOT has used this bridge-moving technique, according to Equipment World. By building the bridge offsite and then moving it into place, agency officials said they were able to complete the bridge installation with fewer interstate closures.
• The bridge replacement is part of an $88 million "Off Broadway" road-widening and reconstruction initiative, the largest project in ODOT history. Crews will now add additional lanes, improve ramps and redesign the drainage system, with work expected to be complete next year.  

Dive Insight:

The technique used for the I-235 railroad bridge replacement, accelerated bridge construction (ABC), represents another example in a growing shift toward prefabrication's use in the U.S. By using ABC, contractors and transportation departments can improve worker safety, as well as the general public's, by reducing distractions and hazards that would normally be present in construction work zones. The method also allows construction to continue with a shortened timeline and with reduced impact on the flow of traffic.

Last June, Tennessee's Transportation Department announced that it would use ABC techniques to carry out the $28.5 million replacement of 24 bridges in downtown Nashville. The Massachusetts Department of Transportation also used ABC when it replaced Boston's Morton Street Bridge. Construction of the bridge took from December 2013 to August 2014, but the bridge was closed to traffic for only nine days.

Perhaps one of the most high-profile ABC cases was C.W. Matthews' and the Georgia Transportation Department's use of the method last summer to fix a portion of Interstate 85 in Atlanta after it was damaged by fire and had to be shut down. The use of ABC and an accelerated concrete curing method allowed crews to compress the schedule and reopen the highway a month ahead of original projections. The contractor not only had to replace 350-feet of interstate but 61 steel beams and 13 columns, according to Equipment World.