This website requires certain cookies to work and uses other cookies to help you have the best experience. By visiting this website, certain cookies have already been set, which you may delete and block. By closing this message or continuing to use our site, you agree to the use of cookies. Visit our updated privacy and cookie policy to learn more.
This Website Uses Cookies
By closing this message or continuing to use our site, you agree to our cookie policy. Learn More
This website requires certain cookies to work and uses other cookies to help you have the best experience. By visiting this website, certain cookies have already been set, which you may delete and block. By closing this message or continuing to use our site, you agree to the use of cookies. Visit our updated privacy and cookie policy to learn more.
search
cart
facebook twitter linkedin youtube
  • Sign In
  • Create Account
  • Sign Out
  • My Account
  • Midwest
  • News
    • Newswire
  • Features
    • Projects
    • Companies
  • Top Lists
  • Current Issue
  • Blogs
  • Submit Your Photos
    • People
    • Projects
    • Events
  • Resources
    • Proposal & Bids
    • Industry Jobs
    • Subscribe
    • eNewsletter
    • Events
    • Advertise
    • Reprints and Plaques
    • Staff Directory
    • Construction Cities
  • ENR Home
  • Other Regions
    • ENR Home
    • California
    • MidAtlantic
    • Midwest
    • Mountain States
    • New York
    • New England
    • Northwest
    • Southeast
    • Southwest
    • Texas & Louisiana
Home » Investigators Seek Answers to Anchor Failures on Minneapolis Bridge
Midwest Construction NewsMidwest

Investigators Seek Answers to Anchor Failures on Minneapolis Bridge

March 9, 2012
John Gregerson
Reprints
One Comment


Now that engineers have determined that a ruptured diaphragm plate led to the failure of a pair of cables on a 2,200-ft cable-stayed suspension bridge in Minneapolis, they are turning their attention to potential causes of the rupture, as well as fractures uncovered on two additional plates in late February.

Photo Courtesy of the Minneapolis Department of Public Works
The Martin Olav Sabo Bridge, a on a 2,200-ft cable-stayed structure bridge in Minneapolis, remains closed as investigators attempt to determine why a diaphragm plate supporting one its cables ruptured.

Meantime, city officials say they are satisfied with results of an October inspection of the Martin Olav Sabo Bridge that assigned its 18 sets of cables and anchors the highest possible rating for soundness and lack of corrosion. The four-year-old bicycle and pedestrian bridge also received top ratings in previous  inspections, which are performed annually and primarily rely on visual analysis, says Minneapolis Director of Public Works Steve Kotke. 

On Feb. 19, a diaphragm plate and two of the bridge's longest support cables were discovered lying on the deck, prompting closure of the structure. Less than a week later, city crews removed a second pair of cables after fractures were uncovered on a second plate. A day later, fractures were discovered on a third plate.

Kotke would not confirm reports indicating the ruptured plate was partially rusted. “During normal inspections we look for rust. Rust is something you expect to see, but we don't know whether rust or corrosion caused the plate to fail,” he says.

Northbrook, Ill.-based engineer Wiss Janney Elstner Associates has completed inspection of the remaining 15 plates and is investigating the cause of the plate fractures. The bridge's designer, San Francisco-based URS Corp., is consulting on plans to remove the fractured plates, says Deputy Director of Public Works Heidi Hamilton.  

Once removed, the plates will be shipped to Bethlehem, Pa.-based Le High University, where they will undergo analysis by John W. Fisher, professor emeritus of civil engineering.

Hamilton says it may take two months to determine the cause of the plate fractures. The initial rupture was of particular significance because it involved the top set of cables on the east end of the structure's 100-ft-high pylon. The cables support a larger section of the bridge than cables located on the west side.

Hennepin County undertook construction of the $5.1-million bridge, but transferred ownership of the structure to the City of Minneapolis in 2008, a year after it was completed. A 220-ft span facilitates continuous biking across the city while accommodating vehicular and light-rail travel on Hiawatha Ave. below.

Hiawatha  was reopened after temporary shoring was installed on the east end of the structure. The bridge remains closed.

ENR Subscribe

Recent Articles by John Gregerson

ENR Texas & Louisiana Project of the Year 2019: Multifaceted Park Adds Up To a Singular Attraction

Glass Welcome Center Becomes Denver Art Museum's New 'Front Door'

The Work Pours In For Water Contractor

Related Articles

Ten Minutes with Howard Hill on the Investigation of the I-35W Bridge Collapse in Minneapolis

Engineers Seek Ways To Warn Of Failures ‘Waiting to Happen’

Related Products

Green Building Materials: A Guide to Product Selection and Specification, 3rd Edition

The Integrative Design Guide to Green Building: Redefining the Practice of Sustainability

Post a comment to this article

Report Abusive Comment


Top Lists

Top Design Firms See a Decline in RevenuesTop Design Firms
Midwest Top Design Firms Still Growing Strong


Top Midwest Contractors: No Recovery In SightTop Contractors
Top Contractors Invest in Expanding Markets, Merge to Grow


Midwest Builders Face Worsening EconomyTop Specialty Contractors
Specialty Contracting Companies See Steady Flow of Business



Industry Jobs

Videos

ENR Proposals and Bids


ENR twitterfeed
Tweets by ENR_MW

ENR

ENR Digital Edition Cover

Dec 9, 2019

A joint venture of Skanska, Corman Kokosing Construction Co. and McLean Contracting Co. is moving toward an early 2020 construction start for a $463-million replacement for a 79-year-old bridge across the Potomac River, south of Washington, D.C.

View More Create Account
  • Resources
    • advertise
    • contact us
    • about us
    • photo submissions
    • customer service
    • digital edition
    • Survey And Sample
  • Subscription Center
    • Subscribe
    • Website Registration
    • Privacy Policy
    • eNewsletters
    • FAQ
  • Multimedia
    • Videos
    • Slideshows
    • Photo Contest

Copyright ©2019. All Rights Reserved BNP Media.

Design, CMS, Hosting & Web Development :: ePublishing