Column: Next big step in bridge project is placing the girders
Mark Anderson is the MnDOT construction project manager for the Red Wing Bridge project. He can be reached at 507-205-6402 or firstname.lastname@example.org. This column is scheduled to run at the first of each month.
A new year will soon mark a new look to the Red Wing Bridge project. Later this month, we will begin deploying the steel tub girders and connecting them between the bridge piers. It's a chore that's tedious, but also comes in bursts of activity to ensure that each piece is placed correctly and secured effectively.
What will happen?
Sections of the tub girders will be delivered via semi tractor-trailer to the south side or Red Wing side of the bridge where they have the area leveled and readied. The truck will back up and one or two cranes will unload the girder.
The first girder from the abutment will be placed on rollers and pushed out to a temporary truss bridge to guide it to Pier No. 1 on the Red Wing side adjacent to the shore of the Mississippi River. Each additional section of the girder will be bolted to the next and then pushed out. Four pieces will make up one set with three sets per span. Each span is expected to take a week to set up and secure.
During this time, work will continue on Pier No. 2, the pier in the river's navigational channel. Then the process will begin again to reach that pier.
Timing is important. We're doing this while the river navigational season is closed, so our interruptions won't impede barge traffic.
Once again, we'll connect the tub girders, this time using cranes instead of the launching method. And each time, we'll secure with temporary bolts, something we call "pinning."
Then it's on to Pier No. 3, where we'll do the work again and get it positioned and set. Once everything is in place, permanent bolts will be installed and given the required torque to ensure its security.
The bridge will still be far from done, but it takes on the form of a more connected structure. We anticipate the work being completed for this portion of the job prior to early March when the shipping season resumes on the river.
I've included some photos that were taken of the tub girders at Veritas in Eau Claire, Wis., where they were manufactured and will be shipped from.
The pieces that will be launched from the south abutment range from 46 feet to 70 feet long by 9 feet tall for a total length of 216 feet. The span over the river is 432 feet with seven sections bolted together, ranging from 9 feet to 14 feet tall. The weight of each section is roughly 140,000 pounds.
This $63.4 million project is a strong partnership that includes the Wisconsin Department of Transportation, the city of Red Wing, the Federal Highway Administration and our contractor, Zenith Tech Inc.
As part of team's efforts, you will see Red Wing City Engineer Jay Owens and me together at various community events or on a bridge tour. We'd be happy to visit with your group or provide your organization or business with the necessary information about the project so you can keep your employees informed. We've found that if you know more about the project, you can help others understand it and minimize any possible disruptions it might cause. We do regular updates on the Community Access Channel 6, so you can catch us there as we provide updates and field questions.
We have a lot of good information that can help explain the project. You can learn more about the project or sign up for email updates by going to MnDOT's project web site www.dot.state.mn.us/d6/projects/redwing-bridge/ or you can follow us on Facebook at https://www.facebook.com/RedWingBridgeProject/.