Gusset plates, deck weight contributed to 35W bridge disaster, NTSB told

[struggle4progress]

Source: Finance & Commerce

November 14, 2008 4:22 PM CST
by Bob Geiger Staff Writer

The weakness of gusset plates, the weight of construction materials and the design of the 35W bridge emerged as prime causes of the structure’s Aug. 1, 2007, collapse during the second day of hearings before the National Transportation Safety Board (NTSB).

Dan Walsh, an official with the NTSB’s highway safety office, said gusset plates holding up the bridge’s center were not considered in bridge load ratings – and only recently have been added to ratings programs by a handful of states.

Joseph Epperson, a safety investigator probing the bridge collapse for the NTSB, told the five-member board in Washington D.C. that existing state and federal design review processes may not be adequate to detect design errors.

When the 35W bridge was built in the 1960s, federal and state government officials counted on the seal of the engineer who signed off on the project, Epperson said. However, the bridge engineer has died and no records exist about why half-inch gusset plates blamed for the bridge collapse were recommended ...

Read more: http://www.finance-commerce.com/article.cfm/2008/11/15/Gusset-plates-deck-weight-contributed-to-35W-bridge-disaster-NTSB-told

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Crucial calculations not done, probe finds
Load-bearing not considered in collapsed bridge's construction
By JON HILKEVITCH Chicago Tribune
Nov. 14, 2008, 11:02PM

WASHINGTON — Critically important load-bearing calculations were inexplicably never performed during the design of a major bridge in Minnesota, setting up the catastrophic collapse of the span last year, a federal investigation concluded Friday.

The error, attributed to the principal design firm failing years ago to properly size steel plates, was the primary cause of the Interstate 35W bridge collapse near Minneapolis on Aug. 1, 2007, the National Transportation Safety Board said in its final report.

Minnesota and federal authorities contributed to the accident, the report said, by failing to properly review the bridge design and also failing to spot during inspections damage that developed in the plates well before the accident.

Even more than a year after the accident, the lessons learned are slow to take effect, investigators warned. Current state and federal design-review processes may not be adequate to detect design errors, the board was told ...

http://www.chron.com/disp/story.mpl/nation/6113614.html

Engineers' lapse sealed fate of I-35W bridge
Calculations that would have detected design flaw apparently weren't done, NTSB says
By Jason Hoppin
[e-mail]
Article Last Updated: 11/14/2008 11:12:10 PM CST

... The bridge collapsed into the Mississippi River just after 6 p.m. Aug. 1, 2007, when a diagonal brace began pushing out against a half-inch gusset plate, flexing it until it snapped. Thirteen people died, and 145 were injured ...

The NTSB issued a host of recommendations Friday that have implications for bridges across the country.

The agency called on states to improve their oversight of bridge designs and rate bridges for load-carrying capacity as soon as they are built. It asked bridge inspectors to begin assessing the condition of gusset plates, and for transportation agencies to check how much weight a bridge can carry before loading construction materials onto it ...

The NTSB believes Sverdrup & Parcel — the St. Louis firm that designed the bridge — did not do all of the necessary calculations on the bridge, basing part of its conclusion on the belief that no competent engineer would allow such a design to be built ...

http://www.twincities.com/ci_10988727?nclick_check=1

State lawmakers react to I-35 bridge report: 'There are more factors to consider'
By G.R. Anderson Jr. | Friday, Nov. 14, 2008

... In New Orleans, Murphy took the time to bend Rosenker's ear about the NTSB's ongoing investigation of why the bridge fell on Aug. 1, 2007.

"I had a conversation with him about the NTSB reports and what other reports had found," Murphy said Thursday night, referring to the state's Legislative Auditor's report on the collapse and another done by Minneapolis law firm Gray Plant Mooty. "I told him to look at those other reports, and that that should be part of their final report."

Instead, as Murphy realized listening to NTSB hearings from Washington on the radio Thursday, it became clear that the chairman did not heed Murphy's advice. At the very least, as the hearings continue today in anticipation of a draft of the NTSB report being released, federal investigators appear intent on their mission to focus only on scientific explanations as to why the bridge fell ...

Murphy understands the mission of the federal board is to look solely at structural issues. But he also believes some answers can be gleaned from what's been issue before. Specifically, Murphy pointed to major findings in both the Legislative Auditor's report and the report by Gray Plant Mooty ...

http://www.minnpost.com/stories/2008/11/14/4623/state_lawmakers_react_to_i-35_bridge_report_there_are_more_factors_to_consider

NTSB findings don't end political debate over bridge
Supporters and critics of the governor and MnDOT find support for views in the report.
By MIKE KASZUBA, Star Tribune
Last update: November 14, 2008 - 8:54 PM

... But critics ranging from legislators to union officials argue that Pawlenty and others ignored the investigation's other findings -- that at the time of the collapse the bridge was loaded with construction materials and equipment in a project supervised by the Minnesota Department of Transportation.

"I think it's more than the gusset plates," said Bob Hill- iker, a former liaison to MnDOT for the American Federation of State, County and Municipal Employees. Hilliker said he was particularly struck by the National Transportation Safety Board's emphasis on the bridge's added construction weight, adding "Somebody had to look at , 'Does the bridge have the capacity to add this weight?'" ...

http://www.startribune.com/politics/state/34497159.html?elr=KArks:DCiUBcy7hUiD3aPc:_Yyc:aUU

NTSB: More Regulations on Bridge Design


Members of the National Transportation Safety Board (NTSB) expressed concern on Friday afternoon that state governments do not perform thorogh reviews on bridge design.

Hours of discussion and testimony went into the two-day NTSB hearing in Washington D.C.

In the end, the five member board unanimously passed several recommendations that will now move forward for the Federal Highway Administration's (FHA) consideration.

The board determined that although there were errors in the bridge's design, the main concern is the lack of proper regulation at both a state and federal level. If these organizations were providing such care, the August 1st bridge collapse into the Mississippi, would never have happened ...

http://www.wdio.com/article/stories/S662847.shtml?cat=10335

First of Many Lawsuits Filed Over Minn. Bridge Collapse
Peter Page
The National Law Journal
November 17, 2008

... The suits were brought by the Minneapolis firm of Schwebel, Goetz & Sieben on behalf of three people who were injured and the family of one person who was killed when the Interstate 35W bridge collapsed into the Mississippi River on Aug. 1, 2007. Wagner v. URS Corp., District Court of Hennepin County, Minn.

"This is a 40-year old bridge that gave out a lot of warnings before it fell into the Mississippi,'' said James Schwebel, attorney for the plaintiffs. "There was bulging and bulking quite visible in photographs as early as 2003, but the engineering firm either did not see that or did not attach enough consequence. The contractor had 587 tons of equipment stored on the weakest point of the bridge when it collapsed."

The collapse killed 13 people and injured 150.

The plaintiffs allege that URS Corp., which was under contract with the Minnesota Department of Transportation to conduct a "fatigue analysis" of the bridge, failed to take action despite documented bulging and buckling of the bridge. URS, represented by Gregory Weyandt of Dorsey & Whitney in Minneapolis, declined to comment on the suit ...

http://www.law.com/jsp/article.jsp?id=1202426051434&pos=ataglance

[uppityperson]

1. k&r& mark to read tomorrow. Thank you for gathering all this.

Car with nieces/nephews went over it shortly before it collapsed.

[machI]

2. Bush Administration spends 2 Trillion dollars on an illegal war in Iraq while Americans die at home

Obama needs to end the war in Iraq immediately and stop the hemorrhage of money being needlessly spent over seas.

Obama needs to create an infrastructure rebuilding program to provide jobs here at home with the money being wasted in Iraq.

I am so glad January 20 will usher in rule by a Liberal President so we can escape these NeoCon pukes.

[MinneapolisMatt]

3. K&R

.

[kickysnana]

4. Spin masters at work; My analysis:

The engineer that built the bridge did not anticipate the total additional weight of the repairs, de-icing and a stupid construction company.

Ditto for whoever approved the design before it was built.

Ditto for the contractor who built it.

I know of people who worked in the DOT and many, many who were competent and loved their jobs left when Molenau became the head of the department, totally unqualified for the job, especially when Pawlenty was elected for a second term. They took other jobs, retired or took early retirement. The agency languished and did not incorporate new technology to do quick reanalysis of existing bridges. Their no new taxes pledge trumped safety.

A graduate student at the U of MN did his thesis on what would cause that specific bridge to fail. He got a job at the federal level of transpiration. That knowledge was readily available.

Resurfacing, shoring up and repair of other structures in the bridge and particularly a deicing system added lots of weight over the years. The bridge structure should have had a complete engineering review during those events.

The contractor who was working on the bridge should have had some rudimentary idea that putting too much weight in any one spot on any bridge was a dangerous plan. DOT inspectors should have also weighed in on the contractors ignorance.

The design was sound for the weight's calculated at the time the bridge was built. The additional gusset plate width would only be necessary if the weight of the bridge changed significantly, which it did.

This means that I cannot trust the administration of the State of MN, nor the current watch dogs of the Federal government to keep me and my loved ones safe. They blame a dead guy and never accept responsibility for the changes and oversight of the changes to the bridge what led to this disaster.

[intaglio]

5. There's a pointed joke engineers make

What's the difference between Doctors and Engineers?

Doctors mistakes only kill one person at a time ... :evilgrin: