Tuesday, January 29, 2008

How would you like your crow prepared, Katie?

Roasted? Probably kind of dry. Fried? That'll make it even tougher to chew. How about stewed in a broth of right-wing bile? That's Spot's recommendation. Tough eating any way you do it.

A week ago, our Katie, yes, crowed about he fact that the NTSB had found that gusset plates were the cause of the I-35 bridge collapse. Move along, people, no government neglect to see here! Spot, of course, had misgivings. So did Nick Coleman, who wrote this even a few days in advance of Katie's bit of triumphalism:

The head of the National Transportation Safety Board says inspections of the Interstate 35W bridge would not have found flaws in the design of the bridge, which opened in 1967. Such inspections would not have learned if Lee Harvey Oswald acted alone or whether the moon is made of green cheese, either.

But the obsolete design of the bridge was known to be flawed long before the bridge fell into the Mississippi last Aug. 1, killing 13 and injuring 145. It was a "fracture critical" bridge, meaning that if any major part failed, the whole thing would fall. It was precisely that lack of redundancy that led worried officials to order stepped up inspections of the "structurally deficient" bridge, which carried 140,000 vehicles a day, pounded by far more traffic than was intended.

So NTSB board chairman Mark Rosenker was disingenuous, at best, when he said "routine" inspections would not have found a flaw in the bridge gussets that the NTSB is blaming for the collapse. "Routine?"

There was nothing "routine" about the bridge, including its inspections. It had so many problems that it was the most-inspected bridge in Minnesota and engineers were openly worried (according to a story in this paper Aug. 19) about the dangers of a collapse.

Inspections did find that many of the gussets were corroded and thinning, plus a host of other significant problems ranging from cracks and missing bolts to a tilted bridge pier and frozen expansion rollers.

The question isn't whether the original designers were distracted by thoughts of Marilyn Monroe as they were planning the bridge. The question is why wasn't the bridge closed, or fixed, by those in charge now?

On Sunday, there was this op-ed piece by Jim Carlson. Carlson is a DFL state senator from Eagan. Now one of the interesting things about Carlson is that he has some credentials:

In her Jan. 21 column ("A new witch to chase in bridge collapse with hunt"), Katherine Kersten is dismissive of anyone questioning the early findings of the National Transportation Safety Board (NTSB). Kersten says, "Suddenly every critic seemed to have an engineering degree in his back pocket." While I do not carry my degree in my back pocket, I do proudly display it on my wall. I also happen to sit on the Joint Committee on the Bridge Collapse.

Ooh, this isn't going to go well for Katie is it, Spotty?

No, grasshopper, it's not. Senator Engineer Carlson had a few observations that are pertinent to Katie little homily on putting the matter to rest:

As a licensed professional engineer, I practiced engineering with a disciplined group of people. We have a code of conduct that discourages uniformed comment or conclusions outside our areas of expertise. Watch the media carefully and you will not see a professional engineer make conclusions on incomplete evidence.

The collapse was not an act of God; it was an error of oversight. Something was missed.

If there was an original design, specification or construction error that compromised safety, it was overlooked several times over 40 years. Lanes, roadway thickness and heavier medians were added, along with 33 percent more traffic, evidently without a verification of load capacity.

After the bridge fell into the river, I began reviewing the many years of bridge-inspection reports. I was surprised to see that problems were often reported for more than a decade without corrective action. There were instances in which the inspectors used exclamation points to draw attention to unaddressed problems. Other reports included many broken bolts and a tipped pier and "significant section loss." However, in its preliminary findings, the NTSB dismisses any factor related to the inspection, maintenance or condition of the bridge as a potential cause for collapse.

As an engineer, I find this unsettling and inappropriate. Does the NTSB not think that broken bolts are warning signs? Does it not think a tipped pier ought to be analyzed? Does it not think that "significant section loss" weakens gussets? Could not adding lanes, road thickness and heavier medians to under-designed gussets be an error?

Boy, those seem like good questions, Spotty!

They do, don't they? And Carlson had this to say about the guy that Katie says has put the whole matter to rest:

Mark Rosenker, the chairman of the NTSB, has also created credibility issues. He is not an engineer. He is a former Air Force general and has been a member of Dick Cheney's staff and a lobbyist. He has also been involved in several Republican presidential campaigns. His rush to pin the blame on a 40-year-old design problem, while ignoring all the other contributing factors, is unseemly at best. He also said that never in the history of his organization had it seen a similar underdesigning of gusset plates; yet in 1996, Ohio discovered gussets that were too thin on a sagging bridge. Since then, Ohio bridge inspectors have been inspecting gusset plate design, which Rosenker also stated inspectors are not trained to do.

This is the guy in charge of the NTSB?

Yes, grasshopper, he is. But even he has had to back away from his smug pronouncements:

The chairman of the National Transportation Safety Board backed off Monday from earlier remarks that seemed to rule out all but design flaws as the "critical factor" in the Interstate 35W bridge collapse.

Mark Rosenker's clarification, made to U.S. Rep. Jim Oberstar, D-Minn., came as NTSB investigators again contacted one of the researchers involved in a study of an Ohio bridge that buckled a decade ago due to undersized gusset plates similar to those that have become the focus of the 35W investigation.

Rosenker, meeting privately with Oberstar, said he did not mean to suggest that the finding of undersized gusset plates on the 35W bridge reflects the board's final conclusion on the cause of the Aug. 1 accident. That conclusion is expected later in the year.

[a chorus from the boys and girls] Bon appétit, Katie!

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