Design Flaw Said to Have Caused Minn. Bridge to Collapse

[babylonsister]

Design Flaw Said to Have Caused Minn. Bridge to Collapse
By Del Quentin Wilber and Michael Laris
Washington Post Staff Writers
Tuesday, January 15, 2008; Page A03


A design flaw caused a Minnesota bridge to collapse last summer, killing 13 people and injuring 100 in an accident that focused renewed attention on the safety of the nation's highways and bridges, according to federal sources familiar with the investigation.

The National Transportation Safety Board is expected to announce today that investigators have traced the failure to steel structures known as gusset plates that held together beams on the Minneapolis bridge, according to sources who spoke on condition of anonymity because they were not authorized to discuss the board's findings.

Some gusset plates on the bridge, which carried eight-lane Interstate 35W across the Mississippi River, snapped during evening rush hour on Aug. 1, leading the bridge to crumple, according to the sources.

Gusset plates are common on steel bridges across the nation, including in the Washington area. They hold together angled beams on the bridge's frame.

The sources said the fault in the Minneapolis span stemmed from the bridge's design and would not have been discovered during detailed state inspections.

When the bridge was built in the 1960s, its gusset plates were not thick nor strong enough to meet safety margins of the era, the sources said. Over decades, renovations added weight to the span. It was undergoing a construction project with heavy equipment and material at the time of the collapse.

more...

http://www.washingtonpost.com/wp-dyn/content/article/2008/01/14/AR2008011402782.html?wpisrc=rss_nation

[Fovea]

1. MN needs a written apology from that

DoT bitch.

Apparently bike and pedestrian facilities were not the culprit.

Let me be the first to wish the US DoT a big Fuck You!

[liberal N proud]

2. Why are tests during construction not standard procedures?

"During the construction projects, the sources said, state officials and contractors did not recalculate how extra weight might affect the gusset plates. They said it was not standard procedure to do such studies."

[qb]

3. How convenient to scapegoat some designer from 50 years ago...

The Star Tribune did an expose a while ago where the contractor hired to do the inspections ran computer simulations that predicted a collapse. The contractor said the bridge must be reinforced ASAP... until someone in Mn/DOT leaned on them to change their story. Closing the bridge for repairs or replacement just wasn't politically expedient.

Maybe it was a design flaw, but what happened in the decades that followed is certainly relevant.

[babylonsister]

4. Thanks. I agree, now it's nobody's fault, is it. Typical. nt

[peacetalksforall]

5. This is a Republican administration and Governor coordinating

a strategy. A design flaw, indeed. It was something that they knew about - it wasn't hidden. Following design and construction you have inspections and repairs. They knew there was a problem. It was studied and analyzed and timetables were known. A Republican Governor didn't want to do it. They postponed it. Plain and simple.

They believe we are fools to think that the design called for never having to watch after it and maintain it or correct anything. They expect us to believe that knowledge and materials of 50 years don't have to be checked and retrofitted.

Don't be misled. Nothing in that announcement exonderates those responsible.