Lowry Avenue Bridge Explained

Bridge Name:Lowry Avenue Bridge
Crosses:Mississippi River
Carries:Four lanes of CSAH 153 (Lowry Avenue North)
Locale:Minneapolis, Minnesota
Design:Basket handle tied-arch bridge, steel
Mainspan:450feet
Open:October 2012
Maint:Hennepin County, Minnesota
Id:27B60
Coordinates:45.0131°N -93.2744°W
Bridge Name:Lowry Avenue Bridge
Crosses:Mississippi River
Carries:Two lanes of CSAH 153 (Lowry Avenue North)
Locale:Minneapolis, Minnesota
Design:Truss bridge
Mainspan:143 feet
Length:889 feet
Width:57.2 feet
Below:33 feet
Open:1905; remodeled in 1958, 2006
Maint:Hennepin County, Minnesota
Id:2723(726)
Traffic:16,600 (2001)
Closed:2008 (demolished 2009)

The Lowry Avenue Bridge is a steel tied-arch bridge over the Mississippi River in Minneapolis, Minnesota, completed in October 2012.[1]

History

The original structure was built in 1905 and utilized a 5-span truss bridge design.[2] This bridge lasted 51 years until it became too weak to carry traffic.

In 1958, five new truss spans were built in this location, using the same piers but raised 20 feet to allow navigation on the upper Mississippi River. This bridge was notable in that it had a steel grid deck where the river was visible directly through the mesh, as opposed to the (currently) more common concrete deck.[3]

Lead-based paint was removed from the bridge during a 2004 repainting effort and the steel grid deck was replaced in 2003. At this time, the bridge was expected to be replaced in the mid-2010s, and community meetings were held in 2007 to choose a design for the new span. However, the timetable to replace the bridge was accelerated as the condition of the 100-year-old piers deteriorated.

During the 2004 repainting, engineers discovered that the pier 3 bearings (east side of navigation channel) had displaced roughly 11 inches east of their original location as a result of unexpected movement of that pier (west) towards the main river channel. Hennepin County contracted with Wiss, Janey, Elstner and Associates (WJE) to investigate and report on the cause and extent of damage. The consultant's report concluded that evidence suggested the pier underwent many years, perhaps 50, of creep deflection due to sustained lateral earth pressure at the foundation which was held in check by the bearing assemblies. The bearing assemblies ultimate strength was finally overcome sometime in 2004 which allowed the unrestrained and rapid movement of the pier. The structural engineers at WJE were unable to predict the magnitude of future pier displacements.[4]

Hennepin County, which owns and maintains the bridge, closed the bridge at 10:00 AM on April 25, 2008, due to safety concerns.[2] [5] Controlled explosions were used to demolish the bridge spans 14 months later on the morning of June 21, 2009.

Construction of the $80 million replacement bridge began early 2010 and was opened for traffic on October 27, 2012, at a cost of $104 million.[6] The bridge includes a protected, 12feet shared-use path on both sides for pedestrians and bikes.[7]

See also

External links

Notes and References

  1. Web site: Rolling out the Lowry Avenue bridge . Finance & Commerce . Drew Kerr . October 26, 2012 . The Lowry Avenue bridge is opening on Saturday, Oct. 27, four years after officials demolished its predecessor. The new bridge includes an anti-icing system, LED lighting and a storm water management system. .
  2. News: Blake . Laurie . Lowry Avenue Bridge . Star Tribune . 2009-06-21 . 2009-06-22.
  3. News: Walsh . Paul . Lowry Av. Bridge coming down today . Star Tribune . 2009-06-21 . 2009-06-22.
  4. LOWRY AVENUE BRIDGE:Investigation of Westward Displacement of Pier 3, 2004 - Wiss, Janey, Elstner and Associates
  5. News: Foti . Jim . Lowry Avenue Bridge to be shut down . Star Tribune . 2008-04-25 . 2009-06-22 . https://web.archive.org/web/20091013141118/http://www.startribune.com/local/18140934.html . 2009-10-13 . dead .
  6. Web site: New Lowry Bridge Still On Track To Reopen In Summer . February 15, 2012 . 18 June 2012.
  7. Johnson, Matt M. Web site: Lowry Avenue Bridge is a new take on the arch . Finance & Commerce . February 15, 2012 . 18 June 2012.