They did not build many bridges in the 1940s to be redundant, which is why so many of them need to be repaired or replaced today.
The U.S. 84 Natchez-Vidalia Bridge, which links Vidalia, La., to Natchez, Miss., is one of those spans in need of attention. The 3,664-ft-long, five-span, cantilever truss bridge features one suspended span and two quasi-suspended spans. A pin and link assembly holds the bridge sections together and over time the pin has “walked itself out” of its proper position.
HNTB devised a solution to vertically post-tension the bridge to take the load off so the pin and link can be removed and replaced. Working with the contractor, HNTB lifted up the two joining sections to transfer the load to a support structure. Once the load was off, the pin was removed and the link freed to be taken away. A new pin and hanger assembly was crafted and installed, and the load transferred back.
To see a video on the project, click here.
