In the infrastructure world, new construction draws the headlines. However, rehab projects are just as vital for many reasons. The I-43 project in Northeast Wisconsin is a rehab project that the Wisconsin Department of Transportation (WisDOT) has undertaken, and it has many benefits.

I-43, a four-lane highway and a major thoroughfare in the area, has an average daily traffic of 52,000 vehicles. The area under construction is spread out over 10 miles and work is focused primarily on 17 bridges.

The design life of these bridges is 75 years, but the only way they will last that long is to perform regular maintenance. In this part of the country, which sees heavy snowfall, roads are regularly salted throughout the winter. The salt not only melts the snow, but it does a number on the bridges. It causes rusting of rebar in the concrete on bridges and concrete spalling in bridge decks.

The bridges were built in the late 1970s. In 2005, they underwent a major maintenance project when an asphalt overlay was put on the original roadway. “This type of work schedule is very typical for what we do for bridges here in Wisconsin,” says Brian Haen, WisDOT Project Manager. In his role, Haen has been engaged in the project from design and will stay on it all the way through the end of construction to keep the project moving.

“The goal of the project is to get at least 20 more years out of the bridge,” says Haen. As part of the project, the contractor – Zenith Tech – will remove the asphalt overlay and then grind into the original deck. They are striving to get the salt out of the original bridges as much as possible. Once that’s complete, the team will install a new concrete overlay and replace any joints that are in poor shape. Where necessary, there are also deck concrete repairs that are being done by hand with jackhammers.

In addition to the concrete overlays, the project will include painting of the bridges’ steel girders. Haen notes this is part of the maintenance, as paint doesn’t last forever. They will also replace a sign bridge that has reached its service life. WisDOT has been slowly replacing these over the years with each construction project. “The maintenance people have concerns about the sign bridges because they are made of cast aluminum and can develop cracks,” says Haen.

The first element of the project is the reconstruction of the shoulders leading into the bridges. A precautionary measure, this is occurring before the work on the bridges. The shoulders will see much more activity during bridge construction.

This is because I-43 will remain open (one lane in each direction) during construction. Traffic will be moved to one side and the shoulder will therefore act as a lane. “The shoulders were not designed to handle the level of traffic they will see during construction,” says Haen. “By beefing up the shoulders coming into the bridges, we believe they won’t fail. Our goal is get out in front of a potential problem.”

To deal with the traffic, WisDOT is using the Queue Warning System (QWS). There are message boards every mile that have a speed sensor that communicates to drivers that traffic is slowing up ahead. As the queue of cars grows, the program takes data from the site, and sends the message back further and further. The goal is to encourage a driver to pay attention and note something is happening ahead, like stopped traffic, and avoid rear ending crashes.

Another issue arose that’s related to logistics. While I-43 will remain open, some on and off ramps will be closed. “The contractor and DOT had a challenge in how to close ramps and still enable people to get to their destinations and maintain access to the entire City of Green Bay,” says Haen. Up to 5 or 6 miles of continuous lane closures straight can be closed at one time.

Zenith Tech, who was selected as contractor by a low bid competent and responsible bidder process, has worked with WisDOT in the past. Haen notes they are one of the half dozen or so bigger bridge builders in the state.

Their experience has been a benefit. The budget of the project is $6.3 million, with a 20/80 split between the state and federal government. The project is currently on budget and running ahead of schedule. “There’s good communication between the state and the contractor,” says Haen. “We are on the same page about how work will progress.”

Another reason for good progress of the project is the weather, which Haen says has, “helped us get more done than we thought we would this construction season.”

Construction began in July 2020 and is scheduled to continue through 2021. The goal is to get the bridge work done by Memorial Day since the roadway draws summer tourist traffic.

Haen also cites the decision to make the concrete on site as a reason for good progress. “The contractor has a specialty truck that self-mixes the concrete overlay on site and pours it right away,” says Haen. “It’s designed for just pouring concrete overlays on decks.”

When the project is complete, commuters will have a more reliable and smoother commute. The closures that periodically occurred due to maintenance issues will be minimized. WisDOT will save maintenance dollars and free up crews to work on other roadways. Plus, the life of the bridge will be extended.