By Nate Herring
Middle East District
WINCHESTER, Va.- Imagine driving a 20-minute detour just to reach the other side of a road. Personnel at the Naval Support Activity located in Manama, the capital city of Bahrain face this on a daily basis when traveling between Naval Support Activity 1 and Naval Support Activity 2. The two areas are divided by a busy roadway.
However, a new flyover bridge that will connect the two areas is being constructed at the installation by the U.S. Army Corps of Engineers, Middle East District.
The flyover bridge, another name for an overpass, will be an approximately 400-foot long tied-arch suspension bridge with a roadway and pedestrian walkway. Construction on the bridge began in September 2012.
"The tied-arch design was utilized so that there would be no bridge supports in the causeway median," said Janet Rigoni, Middle East District project manager. The lack of bridge supports on the roadway is a safer option because it limits hazards for drivers.
One of the greatest challenges for engineers was to avoid closure of the busy road underneath the bridge for extended periods of time. As a result the bridge is assembled at a nearby location and will be moved into place, but moving the 2,500-ton bridge will be no easy task. The bridge, which is currently sitting on temporary supports, will be transported using four self propelled mobile transports. These machines will lift the bridge at its bearing points and safely move it into position. The move is currently scheduled to occur on a weekend in late January 2014. Doing so over a weekend ensures that the impact to traffic on the road below, which will be closed during the move, will be minimal. The closure will be coordinated with the government of Bahrain.
"The method of construction is significant," said Mike Allen, Middle East District structural engineer.
The work does not stop once the bridge move is completed.
"There is still a fair amount of work to be done after the bridge is set on the new bearings, not so much for the bridge but for the surrounding construction," Allen said. That work includes completing the approach ramp and pedestrian ramp pavement, installing expansion joints and safety barriers, installing lighting and security systems, among other things.
This is the first such bridge project like this in the Middle East District's history.
Engineers and personnel from the District spent several years working on the planning, design and construction of the bridge, Rigoni said. "There are many great team members working on this project."
The project was initiated in August 2009 and a part of a large project which also consists of an Explosive Ordnance operations building, small arms firing range and entry control point. The expected completion for the bridge is mid-2014.