Huey P. Long Bridge Main Span Superstructure, Jefferson, LA
The Huey P. Long Bridge Widening is a four-phase project vital to the recovery of Greater New Orleans.
The widening will add an additional travel lane, as well as inside and outside shoulders to each side of the bridge, providing a safer and more reliable crossing over the Mississippi River.With a joint venture, Traylor Bros., Inc. employed an innovative span-by-span erection method to build this project. By utilizing temporary stabilizing frames that span between the bottom chords of the proposed widening trusses, and stabilizing towers to brace the compression chord of the truss while lifting, the joint venture eliminated the need for falsework in the river, with only one exception: the West Bank anchor span, which was constructed with a modified stick build method. The stabilizing frames and trusses were erected on barges and floated into place directly underneath the bridge. The whole system of trusses and stabilizing frames was lifted at the four corners by strand jacks supported on top of the widened pier trusses of the bridge. Therefore, despite the contract anticipating the team delaying bridge and marine traffic, we devised a scheme that allowed preassembly of the bridge, minimally impacting the public. This was a huge win for both the team and the local economy.
This phase of the project consists of .451 miles of a cantilever truss highway and railroad bridge widening with parallel trusses and steel stringers for a widened roadway deck system. The work includes widening the roadways on the 71-year-old span from two nine-foot lanes in each direction to three 11-foot lanes, with appropriate shoulders and fastening on the new trusses. The existing bridge was retrofitted in order to be connected to the 17,500 tons of new steel. 60,000 existing rivets were replaced with high-strength permanent bolts.