AASHTO Journal, 5 February 2016
The Alabama Department of Transportation set out to save months of traffic disruptions when replacing the first of two roadway bridges along SR 210 in Dothan, with plans to use the state’s first bridge slide construction project that would close part of the road for just seven days.
But the work went faster than planned after crews closed the lanes on Jan. 29, and the road reopened with a newly installed bridge in the southbound lanes on Feb. 1 – a full four days early.
The project in Dothan, in the state’s southeastern corner near the Georgia and Florida borders, would have required nine to 12 months of lane closures and traffic detours if the agency had used traditional in-place construction methods, ALDOT said.
The work is part of a widening of SR 210, also known as Ross Clark Circle. When it was first built in 1955, that highway section handled 5,000 vehicles per day. Now it carries more than 40,000 daily and traffic often backs up.
To help ease congestion, ALDOT is widening the Circle from four to six lanes in staged projects. When it opted to build two new bridges, one in each direction, it also determined that normal-length closures would disrupt both local and tourist traffic.
So, said the project website, ALDOT introduced “something never before seen in Alabama,” the bridge slide. The bridges are built on temporary supports parallel to the existing active roadway. When all is ready, crews slide or roll the bridge sections into place with powerful jacks.
The agency set up detours but maintained access to businesses in the construction area. “We understand the importance of resuming traffic in the area as quickly as possible,” it said as it announced lane restrictions.
It also encouraged those who might want to see the slide technique to view it on a live video feed on the project website, to keep more people away from the construction zone.
After traffic resumed Feb. 1, ALDOT said that “officials credited efficient construction practices and good weather for lanes reopening four days ahead of schedule.”
And it immediately turned its attention to the next phase: “Officials will now begin plans to work on the northbound bridge slide. This schedule will be announced once those plans are finalized.”
