When a bridge in Houma, La., that had been unused for nearly 20 years had to come down for safety and obstruction reasons, the decision was made to relocate it to Freeport, Texas, where an existing bridge needed to be replaced.
The entire Houma Bridge was then dismantled and secured onto seven barges and shipped to Freeport through the Gulf Intracoastal Waterway.
“Constructing a movable bridge while maintaining rail and marine traffic is always challenging and requires experts in many disciplines,” says Ralph Eppehimer, senior associate at Modjeski and Masters. “The team on this project had the additional complexity of dismantling and moving the lift bridge before rebuilding it. The ability to disassemble and ship the bridge on the barges in large sections made the project very efficient.”
Modjeski and Masters led the design of the relocated bridge, and the project was completed in 15 months.
“An innovative feature of the bridge replacement was the temporary ‘bobtailing’ of the old swing span in Freeport prior to its removal to provide the necessary clearance for erection of the north lift span tower,” Eppehimer says. “The ‘bobtail’ modification consisted of shortening one end of the swing span by two truss panels and rebalancing the span so that it could remain in operation until its replacement with the lift span.”
Owner: Union Pacific Railroad, Little Rock, Ark.
General Contractor: PCl Cos., Tampa, Fla.
Lead Design: Modjeski and Masters inc., New Orleans
Structural: Modjeski and Masters inc.