could result from replacing the road surface. Like so many
other things with this project, that work was far from
routine. Most bridges are straight; their sides are parallel
throughout. The Richard I. Bong Memorial Bridge is “S”
shaped and the approaches are more complicated than
“The load rating was complex because of this bridge’s
unique alignment and flared geometrics,” Pantzlaff said.
“The Minnesota approach in particular has complex
geometry. We also performed a load rating for the arch
itself. The tied arch is a unique structure; it behaves
different structurally. The load rating got to be quite
sophisticated. Our structural engineering analysis
revealed that the bridge had plenty of capacity for
vehicles, even after the additional load from the concrete
The project included milling off 2 inches of deck surface
and overlaying the deck with new concrete. That’s
600,930 square feet of bridge decking – equivalent to
more than 13 acres (or, for the sports-minded, more
than 10 football fields). Crews repaired sidewalk edges,
updated lighting, and repainted surfaces. A structure
as large as the Richard I. Bong Memorial Bridge will
expand and contract depending on temperatures, and
the project included replacing the 24 sets of joints that
accommodate those movements.
The center span of the bridge is a 500-foot-long, 80-foothigh, steel tied arch. Each supporting cable in that span
was inspected, repaired, and adjusted as needed – a fairly
involved process, Pantzlaff noted.
While crews were working on the bridge, another crew
was improving the Wisconsin side approach. Ayres
designed the 1.3 miles of approach, including realigning
a portion of the highway that crosses the bridge – U.S.
Highway 2 – with Belknap Street, a major thoroughfare
in Superior. Ayres’ design work included design of a
multilane roundabout at the intersection of U.S. Highway
2 and Belknap Street to replace several intersections.
This roundabout is the first roundabout for the City of
Superior. Mayor Bruce Hagen supported construction of
the roundabout from the start.
“Consider safety, cost, efficiency, and the maintenance of
a signalized intersection as years go by,” he said. “I think
it’s a wonderful addition to the community.”