By Yanling Leng, PhD, PE

The Benson Road bridge in Sioux Falls, SD was in disrepair. More than 20% percent of the 453-foot, six-span deck was delaminated, but a total bridge replacement was too costly.

The city opted for a $4.4 million deck replacement instead — the first project of its type in the state since 1985.

Replacing a deck while keeping the original superstructure and substructure can be a more affordable option than replacement.

But one challenge is removing the old deck without damaging the girders underneath – damage that can create costly delays.  The Benson Road project’s success can be attributed to the implementation of best practices and a strong focus on quality assurance and quality control throughout the process.

IMEG also wanted to maximize the service life of the Benson Road bridge’s new deck, so we specified zinc, epoxy dual-coated reinforcing steel, and stainless reinforcing steel. These materials will protect against damage from deicing chemicals used by the city in the winter months.

The U.S. has a large backlog of bridge repair work, and most states and municipalities have limited budgets for repair or replacement. In the right circumstances, choosing a deck replacement can take less time and cost less than bridge replacement.