Tag Archives: Virginia Minnesota

Bridge Construction, Bridge Foundations, Drilled Piles, Drilled Shafts, Foundation Design, Micropiles, Miscellaneous, Rockfall Hazard, Slope Stability

Two Major Bridges in Minnesota Open to Traffic

St. Crox Crossing Extradosed Bridge; photo courtesy of MnDOT

Two DBA bridge projects in Minnesota opened to traffic recently.  The St. Croix Crossing near Stillwater and the Highway 53 Relocation in Virginia.  Both projects are milestones for MnDOT.  The St. Croix Crossing is the first extradosed bridge in the Midwest and only the second extradosed bridge in the United States.  The new Highway 53 Bridge is the tallest bridge in Minnesota.

Following a ribbon cutting and dedication ceremony on the morning of Wednesday, August 2nd, the St. Croix Crossing saw its first traffic later that evening and has already alleviated traffic congestion  in downtown Stillwater,  as intended.  The interstate project was also heralded as a noteworthy example of government cooperation by The Wall Street Journal.

After officially breaking ground just shy of two years ago,  the new Highway 53 bridge opened to traffic on September 15th.  A dedication ceremony was held underneath the bridge that morning with Minnesota Lt. Gov. Tina Smith and Congressman Rick Nolan in attendance.  In  anticipation of the new bridge, the iron range quad cities of Virginia, Eveleth, Gilbert, and Mountain Iron held a four-day, multi-event festive, Bridge Daze, in August.

Hwy 53 Bridge Across The Rouchleau Pit; photo courtesy of OxBlue construction cameras
Bridge Construction, Bridge Foundations, Foundation Design, Foundation Testing, Load Testing, Micropiles, Slope Stability

DBA Engineers Perform “Extreme” Geologic Investigation

DBA engineers prepare to go over the edge of the 200-ft tall west wall of the Rouchleau mine pit with the load test site in the background. From left to right: David Graham, Nathan Glinski, Ryan Turner, and Paul Axtell
DBA engineers prepare to go over the edge of the 200-ft tall west wall of the Rouchleau mine pit with the load test site in the background. From left to right: David Graham, Nathan Glinski, and Paul Axtell (far right).

DBA is currently working with structural designer Parsons to design what will be Minnesota’s tallest bridge.  The bridge will span the currently inactive Rouchleau open pit iron ore mine near Virginia, Minnesota. MnDOT is moving the alignment of the existing Hwy 53 to make way for future mining in the area.  DBA is the lead geotechnical designer on the project in addition to being contracted as MnDOT’s load test expert for the ongoing design phase load test program.

As part of our site investigation to gather information on rock fall and the site geology, five DBA engineers (John Turner, Paul Axtell, Tim Siegel, Nathan Glinksi, and David Graham) got up close and personal with the site by rappelling off the near vertical cut faces on either side of the Rouchleau pit! Traversing the over 200-ft tall cut faces of the nearly 2-billion year Biwabik Formation rock formation by rope and harness, we collected valuable geologic data.  We also took some great pictures like the ones posted to our Google Photos account.  In addition to the still pictures, we took some videos of a few rock fall tests, which are on our YouTube channel.

If you would like to know more about this interesting project on Minnesota’s Iron Range, you can check out our project summary sheet, visit MnDOT’s project page, or stay tuned to this blog for more updates.  There is also an online article about the project that was recently published by Civil Engineering Magazine.