Rapid bridge replacement

Thermal lance cutting away a railroad bridge in Binghamton, New York to prepare for its replacement.

Self-propelled modular transporters moving Hamilton, Ontario's Aberdeen Bridge span into place.

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.^[1] 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 crammed into the other bridge half, often for a year or more, while construction progresses.

Notable rapid bridge replacement projects include Interstate 93 in Massachusetts, where 14 bridges were replaced over 10 weekends in 2011.^[2]

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