Rapid bridge replacement

Rapid bridge replacement or accelerated bridge construction (ABC) is a technique that allows bridges to be replaced with minimum disruption to traffic. The replacement bridge is constructed on a site near the bridge to be replaced. When it is completed, the old bridge is cut away and removed using self-propelled modular transporters (SPMTs). Then the SPMTs lift the new bridge, transfer it to the work site and put it in place. Often the highway or railroad carried by the bridge is closed for just one weekend. Conventional techniques typically replace half a bridge at a time, with all highway traffic redirected under the other bridge half, often for a year or more, while construction progresses.
Accelerated Bridge Construction(ABC) alternatives consist of ABC components and ABC techniques. Components can be categorized into prefabricated bridge elements (e.g. beams, bridge decks, footings, columns, pier caps, abutments etc.) or prefabricated bridge systems (e.g. bridge modules with superstructures and/or substructures). ABC involves fabrication of these elements or systems off-site in a regulated environment, and transporting those to site for installation. Related processes such as lifting, placement, transportation, embankment construction are termed as ABC techniques.

Notable rapid bridge replacement projects include Interstate 93 in Massachusetts, where 14 bridges were replaced over 10 weekends in
2011.

Incidents
On March 15, 2018, a partially completed bridge at Florida International University collapsed five days after it was placed using this method. FIU is home to the Accelerated Bridge Construction University Transportation Center, a federally-funded center. It is known for its expertise in the field, has attracted top international scholars as PhD students, and sponsors industry conferences and seminars. That week, FIU was planning an independent investigation into the cause of the collapse.

References

Category:Bridge maintenance