ASPIRE is a quarterly magazine published by PCI in cooperation with the associations of the National Concrete Bridge Council. The editorial content focuses on the latest technology and key issues in the Concrete Bridge Industry.
Issue link: http://www.aspiremagazinebyengineers.com/i/297024
Ample new access provided for pedestrians, snowmobiles, cars, and the Zumbro River Zumbrota, Minn., is the quintessential quiet little town, tucked into the southeaster n cor ner of the state between Minneapolis/St. Paul and Rochester. While it may be small, the town relies on its transportation i n f r a s t r u c t u r e a s m u c h a s a n y l a r g e m e t ro p o l i t a n a re a . A n d a m a j o r c o m p o n e n t o f Z u m b ro t a 's transportation system is the bridge that carries Minnesota Trunk Highway 58 (T.H. 58) over the North Fork of the Zumbro River. With a 23-mile detour t o t h e n e a re s t a l t e r n a t i v e t r u n k highway river crossing, a closure of the T.H. 58 bridge would affect a variety of transportation users including residents going about their daily business, school buses, farm-to-market truckers, and commuters to the town's larger neighbors. Along with its functional importance, the crossing also has historical and social significance to the local community. The T.H. 58 crossing was closed, however, in 2010 while the Minnesota D e p a r t m e n t o f Tr a n s p o r t a t i o n (MnDOT) had a replacement bridge built. The new bridge, Bridge 25025, was necessary for the usual reasons. Its predecessor, Bridge 5188, was both functionally obsolete and structurally d e f i c i e n t . T h e s t e e l b e a m s a n d concrete deck had suffered significant deterioration, its sufficiency rating had dropped to 18.4 (on a 100-point scale), and its inventory rating was only HS-11 (for comparison, new bridges in Minnesota are designed for approximately HS-25). This was not a routine bridge replacement project, however. Several challenges had to be overcome, and a variety of design and community issues had to be addressed by the project team. Local Meaning of Bridge The existing bridge, Bridge 5188, did not have an official historic designation. However, the bridge site had major historic significance because of the predecessor to Bridge 5188. When it was built in 1932, Bridge 5188 replaced a covered bridge that had been built in 1869. Instead of being demolished, the covered bridge was removed intact and stored for many years. It was refurbished in the 1990s, and in 1997 it was once again erected over the Zumbro River at a trail crossing approximately 300 ft upstream. The Zumbrota Covered Bridge is the only historic covered bridge in Minnesota and is a source of great pride for the Zumbrota community. The Covered Bridge's replacement also had special meaning for the community, especially the area's military veterans. Bridge 5188 had a plaque on its profile VETERANS MEMORIAL BRIDGE (BRIDGE NO. 25025) / ZuMbROTA, MINNESOTA BRIDGE DESIGN ENGINEER: Minnesota Department of Transportation, Oakdale, Minn. RoADWAy AND PRELIMINARy BRIDGE DESIGN ENGINEER: Yaggy-Colby Associates, Rochester, Minn. PRIME CoNTRACToR: Minnowa Construction, Harmony, Minn. PRECASTER: Cretex Concrete Products, Maple Grove, Minn., a PCI-certified producer AWARDS: 2011 PCI bridge Design Awards, best bridge with Main Spans up to 75 ft by Todd R. Stevens, Minnesota Department of Transportation Zumbrota Veterans Memorial Bridge View of Veterans Memorial Bridge showing bench provided for a future trail. Photo: MnDOT. 16 | ASPIRE , Spring 2012 P R O J E C T Book_Spr12.indb 16 4/3/12 9:18 AM