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Monday, April 07, 2008

Chicken Little - The sky is falling! The bridge has fallen! --- So, you tell me, was Chicken Little asleep at the switch?

photo credit, here

The I-35W bridge fell, August 1, 2007. And so, ostensibly, the Elwyn TInklenberg Congressional candidacy began this cycle, with Tinklenberg previously disclaiming intent to run. Ostensibly, the candidacy was not being planned with endorsements lined up and all before the "falling," with Tinklenberg and Bill McCarthy having heads together earlier for a Congressional run, as a paired holdover from 2006. For those unfamiliar with the name, Bill McCarthy, he is a "voice" in the DFL, due to union ties.

Yeah. Sure. If not for the bridge, we'd have Bob Olson running against Michele Bachmann and Tinklenberg quietly continuing his "consultancy" cash-cow milking in the north metro, but not a candidate - and ostensibly only a candidate once the bridge fell. He says so, so believe it. Just as he seems to say he's not a lobbyist, but only depending on how you define "lobbyist." Believe the man.

The latest Tinklenberg bit on that "bridge fell - I run" theme, less opportunistic than earlier right after the event, about the bridge falling, but still using it as the launch-pad starting line in his opportunistic, Gordon Gecko like, earmarks-are-good St. Cloud Times March 31, 2008 op-ed opinion piece:

Your turn: Earmarks can be necessary
By El Tinklenberg Blaine

Eight months ago, the Interstate Highway 35W Bridge in Minneapolis suddenly collapsed. In a short time, earmarked federal funds were pledged to its rebuilding.

Today, the infrastructure supporting the span of the DeSoto Bridge across the Mississippi River in St. Cloud has been questioned, and federally earmarked funds may be needed to build a replacement.

When 6th District Rep. Michele Bachmann recently pledged not to use the earmarking process to obtain federal funding, she could not have foreseen the emergency closing of a bridge in the heart of the largest city in her congressional district.


In fairness -- My understanding is Bachmann is not opposed to projects being funded in the district and has recently circulated a two-page solicitation letter to local officials including a form for them to use and return to her if they would want to suggest worthwhile projects - i.e., with her objection being to the process yielding waste and dumb projects, anonymously sponsored and dropped into bills, and not to funding of meritorious things in or out of the district but with sponsorship duly disclosed and not hidden under a hat.

Tinklenberg's op-ed piece continued, much in general agreement with the Bachmann position but with a charge of partianship-inspired tunnel vision:

Therein lies the problem with taking extreme political positions that leave no room for the unexpected.

The Office of Management and Budget generally defines earmarks as "add-ons" to a general appropriation that direct additional spending to a very specific project. The problem being that too often the earmarks are "dropped" into committee reports and never seen by most of the Congress.

In 2005 earmark appropriations were estimated to total $18 billion. It was then that President Bush urged the Congress "to reform the budget process and expose every earmark to the light of day ... ."

The now-infamous $223 million "bridge to nowhere," in Alaska (almost as long as the Golden Gate and higher than the Brooklyn Bridge but only connects the 50 or so residents of Gravina Island to a city of 8,000), was an earmark obtained by Alaska Republican Congressman Don Young and often used as an example of earmarking excess.

Yet instead of citing the abuses of Young, Bachmann often is critical of Minnesota colleagues such as Jim Oberstar and Colin Peterson, who understand that earmarking is a legitimate response to important needs such as the I-35W bridge.

[...]

In fact, the emergency situation created by the closing of a bridge across the Mississippi in St. Could is a classic example of a time when earmarked funds can be an appropriate process. With what we know now, it's not clear that the DeSoto Bridge can be repaired, and there is some speculation it may stay closed until it can be replaced.


It's called "risk averse" learning curve. But, risk aversion need not be hammered home by a catastrophe such as the I35W happening. It can, in the rightly disposed minds, be something based on foreseeable risk and respect for lives and safety at risk, should an arguably foreseeable event actually happen - and that rightly disposed intellect can and should arise from good judgment in advance of catastrophe and not in 20/20 hindsight of an aggressive, ambitious, and opportunistic career politician suggesting somebody at a different level of government should pick up the tab or be held responsible if they decline. Tinklenberg's op-ed continues:

Originally scheduled to be replaced in 2016, that schedule could be accelerated if federal dollars could be secured to help pay for a new bridge; however, that appropriation would be an earmark — hence, the problem with Bachmann's pledge to not take earmarks for her district.

The next time Bachmann thinks about swearing off federal funds for our district, she might first contemplate a piece of advice from Winston Churchill: "It's always wise to look ahead, but difficult to look further than you can see."


The big question - what was there obvious to be seen, in past times, but ignored for reasons only the man at the switch can try to justify?

Was Chicken Little asleep at the switch?

Should Chicken Little back during the Ventura administration have been more attentive to heavily-traveled bridge usage and less in love with other pet cost-overrun projects and questionable practices that a past Strib series highlighted and analyzed in some detail - but with the Tinklenberg responsibilities largely overlooked after the series had run its course.

So back to the question - asleep at the switch? Or worse - Gambling unreasonably with the lives and safety of others (as arguably is the case with taconite tailings as paving aggregate before the safety and health issues are definitively resolved)?

You be the judge.

Or try to judge. Or, ideally, Strib and/or PiPress will track down a few study authors with the, "What did you know and when did you know it," question along with the, "What did MnDOT head Elwyn Tinklenberg know, when did he know it, and what did he do or fail to do, and why," question.

First, mainstream media, if doing its job, would find engineers to explain a few studies for background before asking people questions - i.e., learn what to be asking. Then, ask the folks who wrote the materials - "What was your purpose, your hope, why were you funded, and were you satisfied or frustrated by the Tinklenberg-MnDOT attention and action once your efforts were concluded and your final report was published?"

Here is detail.

But first - I have a problem. I do not claim to be a civil engineer, a mechanical engineer, nor a bridge engineer.

However, there clearly are reports suggesting things needing an answer, from during the Tinklenberg tenure as MnDOT head, and suggesting those who have the engineering skills also had "concerns" that received inadequate top-man attention.

These "concerns" are evidenced in reports, which someone with more experience than me needs to dissect.

But here's the evidence for whoever wants to have a look. All from the Tinklenberg tenure as head of MnDOT. Start with the most direct, then the related (and only the online abstracts will be highlighted, with each final study report a MnDOT technical report available online, in Adobe pdf format, at the website links given):

1. This pair of links, here and here, for starting date info and intent, and then for wrap-up final reporting, respectively:

Fatigue Assessment of Deck Truss of Bridge 9340 TH I35W over the Mississippi River
Principal Investigator:
Robert Dexter, Former University Researcher, Civil Engineering

Project Summary:
The deck truss of Bridge 9340 has plug welds, cover plates, and welded clips at diaphragms inside tension members among other poor fatigue details. In addition, there are only the two planes of the truss holding up eight lanes of traffic, so lack of redundancy is a major concern. A quick assessment of the details indicates that many of the details are Category D and E with threshold stress ranges of 7.0 and 5.6 ksi respectively. The analysis shows live load stress ranges in the truss members much higher than these thresholds. With 15,000 trucks per day crossing the bridge in each direction, these details should have already cracked if the stress ranges were really this high. Fortunately, when bridges are instrumented and the live-load stress ranges are measured, it is usually found that the ratio of measured stress ranges to calculated stress ranges is typically 0.5 or less. If, as suspected, this is the case with Bridge 9340, the remaining fatigue life may be much longer than anticipated, and might even be considered infinite. The bridge will be inspected and previous inspection records examined to document all poor fatigue strength details in members with fluctuating load at least partly in tension. Two tension chord members at the peak positive moment region of the middle span of the truss will be instrumented as well as a floor truss. In all, at least 24 strain gages will be installed and monitored during test runs with a truck of known weight as well as monitoring open traffic for several weeks during summer and another several weeks during the winter. A ratio of the measured to calculated stress will be estimated for the components instrumented. These ratios will be applied to the calculated stress ranges at other details, and a fatigue assessment of the worst details with the highest actual stress ranges will be performed.

Sponsor: Minnesota Department of Transportation

Project Details:
Start date: 05/1999
Project Status: Completed
Research Area: Infrastructure
Topics: Bridges and Structures
Reports or Products:
"Fatigue Evaluation of the Deck Truss of Bridge 9340" (2001)

***
Fatigue Evaluation of the Deck Truss of Bridge 9340
Robert Dexter, Heather O'Connell, Paul Bergson
March 2001
Report no. Mn/DOT 2001-10

Projects: Fatigue Assessment of Deck Truss of Bridge 9340 TH I35W over the Mississippi River
Topics: Bridges and Structures

Abstract
This research project resulted in a new, accurate way to assess fatigue cracking on Bridge 9340 on I-35, which crosses the Mississippi River near downtown Minneapolis. The research involved installation on both the main trusses and the floor truss to measure the live-load stress ranges. Researchers monitored the strain gages while trucks with known axle weights crossed the bridge under normal traffic. Researchers then developed two-and three-dimensional finite-element models of the bridge, and used the models to calculate the stress ranges throughout the deck truss. The bridge's deck truss has not experienced fatigue cracking, but it has many poor fatigue details on the main truss and floor truss system. The research helped determine that the fatigue cracking of the deck truss is not likely, which means that the bridge should not have any problems with fatigue cracking in the foreseeable future. As a result, Mn/DOT does not need to prematurely replace this bridge because of fatigue cracking, avoiding the high costs associated with such a large project [based on fatigue cracking, but not other aspects?]. The research also has implications for other bridges. The project verified that the use of strain gages [sic] at key locations combined with detailed analysis help predict the bridge's behavior. In addition, the instrumentation plan can be used in other similar bridges.


So, what in response did Elwyn Tinklenberg, head of MnDOT do? If anything, besides pushing the Hiawatha line? Was he risk averse enough at the time? Or too foolhardy? In hindsight, he should have done more, that is clear, but - as one seeking the trust of an electorate in Congress - is he right for that austere job? Or too inattentive, and too foolhardy with the well-being of others? Now, his op-ed tune is clear. Be risk averse about the St. Cloud situation. But should we want a Congressman who needs this kind of learning experience history to be making our nation's key decisions? Do we want somebody who apparently only can learn things the hard way? And who then uses learning to attack and insinuate things about another, but apparently not to reflect cautiously upon his own past decisions?

You be the judge, if you vote in Minnesota's Sixth District.

Here and here, is more evidence - first, monitoring in general:

2.
Analysis Tools and Rapid Screening Data for Distortional Fatigue in Steel Bridge Girders
Principal Investigator:
Arturo Schultz, Associate Professor, Civil Engineering

Project Summary:
Fatigue Cracking often occurs in composite bridges with unstiffened girder web gaps at the ends of transverse stiffeners. In this project, researchers sought to better understand bridge diaphragm deflection behavior and advance the ability to estimate web gap distortional stress. Trends from the parametric studies led to general observations that may assist in identifying fatigue-prone bridges. Variables that influence diaphragm deflection behavior include girder spacing, bridge skew, span length, and deck thickness. Transverse load distribution properties appear to play the most significant role in determining the magnitude of differential deflection. Parameter study stress trends indicate that out-of-plane distortional stress in fatigue prone web gaps primarily depends on web gap properties, bridge span length, and angle of skew. Differential deflection and web gap dimension trends apply to a varied spectrum of bridge configurations. The research resulted in a method to assess bridge girder differential deflection and distortional stress in actual steel bridges without complex analysis and modeling. Proposed procedures for evaluating out-of-plane stress should prove practical and aid in screening, identifying, and assessing bridges vulnerable to distortion-induced fatigue cracking. 1

Sponsor: Minnesota Department of Transportation

Project Details:
Start date: 08/2000
Project Status: Completed
Research Area: Infrastructure
Topics: Bridges and Structures
Reports or Products:
"Analysis Tools and Rapid Screening Data for Distortional Fatigue in Steel Bridge Girders" (2001)

***
Analysis Tools and Rapid Screening Data for Distortional Fatigue in Steel Bridge Girders
Evan Berglund, Arturo E. Schultz
November 2001
Report no. Mn/DOT 2002-06
Projects: Analysis Tools and Rapid Screening Data for Distortional Fatigue in Steel Bridge Girders
Topics: Bridges and Structures

Abstract
Fatigue Cracking often occurs in composite bridges with unstiffened girder web gaps at the ends of transverse stiffeners. In this project, researchers sought to better understand bridge diaphragm deflection behavior and advance the ability to estimate web gap distortional stress. Trends from the parametric studies led to general observations that may assist in identifying fatigue-prone bridges. Variables that influence diaphragm deflection behavior include girder spacing, bridge skew, span length, and deck thickness. Transverse load distribution properties appear to play the most significant role in determining the magnitude of differential deflection. Parameter study stress trends indicate that out-of-plane distortional stress in fatigue prone web gaps primarily depends on web gap properties, bridge span length, and angle of skew. Differential deflection and web gap dimension trends apply to a varied spectrum of bridge configurations. The research resulted in a method to assess bridge girder differential deflection and distortional stress in actual steel bridges without complex analysis and modeling. Proposed procedures for evaluating out-of-plane stress should prove practical and aid in screening, identifying, and assessing bridges vulnerable to distortion -induced fatigue cracking.


Okay, did the top-dog diddle, or put the monitoring program into effect, and if the latter, what warning of potential danger did the public receive? Were folks mushroomed? Last item, and here is where a different bridge was studied, and I am too ill-informed of the engineering to be able to know if the I35W bridge was of the kind studied or not, or fit to be monitored as suggested based on this study [in light of the very first item, and its I35W specific focus], see: here and here.

And consider this last item in light of the 2003 photos Strib published a week or two ago showing obvious gusset bending at the I35W gussets that NTSB had earlier identified as built at half the thickness that plans specified without anyone at MnDOT publicly acknowledging that fault until after the thing fell, killing and injuring people. When did Tinklenberg know of the bending and the half-the-thickness-it-should-have-been; and when, in exercise of due diligence, should he have known and acted differently than he did [doing something instead of nothing, apparently]?

3.
Remote Monitoring of Distortional Fatigue in Multi-Girder Steel Bridges
Principal Investigator:
Arturo Schultz, Associate Professor, Civil Engineering

Project Summary:
A remote monitoring and assessment program for a multi girder steel bridge on skew supports and typical of those found throughout Minnesota is proposed to quantify the magnitude of distortional fatigue stresses in the girder webs at the connection to diaphragm plates in the negative moment region of the girder. Vulnerability to distortional fatigue in steel plate girders of multi girder bridges exists when diaphragm connection plates are attached to the girder webs but not to the flanges. The magnitude of distortional stresses is worsened by skew supports, fixity of the tension flange in the negative moment region, and stiff diaphragms. To date, instances of distortional fatigue cracking have not been reported in Minnesota, but the MT/DOT Office of Bridges and Structures has ascertained that highway officials in other states have begun to observe cracks at the weld between diaphragm connection plates and web plates in skew, multi girder steel bridges. The proposed work is designed to collect representative field data on the magnitude and frequency of out of plane bending stresses at web diaphragm connections of typical interior and exterior girders in multi girder bridges on skew supports. A research team comprising faculty, staff and students of the Department of Civil Engineering at the University of Minnesota proposes a program to instrument and monitor a typical multi girder steel highway bridge on skew supports and assess the frequency and magnitude of distortional fatigue stresses in the web plates, as well as to evaluate the impact of these stresses on fatigue life. As art of the proposed study, an existing multi girder steel highway bridge which is typical of bridges throughout Minnesota will be elected for instrumentation in the Twin Cities greater metropolitan area. Field instrumentation will be used to monitor the strain changes at critical locations in the selected bridge, and an existing remote monitoring data acquisition system will be upgraded usin

Sponsor: Minnesota Department of Transportation

Project Details:
Start date: 07/1998
Project Status: Completed
Research Area: Infrastructure
Topics: Bridges and Structures
Reports or Products:
"Distortion-Induced Fatigue in Multi-Girder Steel Bridges" (2000)


***
Distortion-Induced Fatigue in Multi-Girder Steel Bridges
Dmitri Jajich, Arturo E. Schultz, Paul Bergson, Theodore Galambos
May 2000
Report no. Mn/DOT 2000-16
Projects: Remote Monitoring of Distortional Fatigue in Multi-Girder Steel Bridges
Topics: Bridges and Structures


Abstract
This report summarizes the findings of a project with the following goals: 1. to implement a field instrumentation and monitoring program for a typical multi-girder steel bridge on skew supports that may be susceptible to web-gap distortion; 2. to assess the frequency and magnitude of the distortional fatigue stresses at the web-stiffener connections; and 3. to evaluate the impact of these stresses on fatigue life. Measurements from 12 independent strain gauges were continuously monitored and recorded for more than three months on Minnesota Department of Transportation (Mn/DOT) bridge #27734. [Where's that one, since it is not bridge 9340, the one over the Mississippi that fell - and is it comparably constructed, wrong gusset thickness and all?] Truck loading tests also were conducted. Predicted web-gap fatigue life based on the long-term monitoring data from Mn/DOT bridge #27734 ranges from 45 to 75 years. Comparison of web-gap stresses with primary design stresses reveals that web-gap distortional stresses are comparatively high. The report also highlights a detailed finite element study to better understand the web-gap stress mechanism and to compare experimental results with theoretical predictions. Study results have important implications for investigators of distortion-induced web-gap fatigue. They indicate that the actual stress at the so-called hotspot may be as much as twice the stress measured at the strain gauge. The report includes a method for estimating girder deflections and web-gap stress.


I have highlighted the identities of study heads and participants. They, along with Elwyn Tinklenberg, should be questioned. They should be asked about their expert opinions of what they believe a reasonably prudent head-highwayman should have done in light of their studies and results. Tinklenberg should then be asked what he, in fact, did, and why he was not more risk averse and why he did not act in a way more protective and aware of public safety and well being.

And - were denser than other aggregate taconite tailings used in bridge resurfacing, and should any extra loading via resurfacing have been done at all on the I35W bridge in light of its study history and the documented photos of bending gussets? What part of that was misjudgment during the Tinklenberg watch, what part truly was the responsibility only of others?

_________

BOTTOM LINE: Sure, the thing did NOT fall during his watch.

But it certainly seems it AS LIKELY AS NOT MIGHT HAVE.

So-

What's the story now Elwyn?

Blame Molneau and Pawlenty?

Blame Michele Bachmann's opposition to the earmark process?

What, Elwyn, about the man in the mirror? Every morning when you shave?

"Oh, him, totally blameless. And loveable. Vote for him. He's endorsed."

That does not cut it, ET.

Explain things.

Don't continue hiding when you should be disclosing detail, and explaining thought processes and decision criteria.

_________
In closing, one side thought - ignoring mainstream heavily-traveled bridge safety while having the history of pushing the Hiawatha and Northstar projects, that IS the Tinklenberg legacy.

The need for mass-transit fitting our being in the 21st century, I agree fully with that, but - Elwyn, what of priorities when you have limited resources available?

The gaudy show pieces, or keeping the bridges safe?

Northstar, we know the man has been paid cash to lobby for it, to promote a stop in Ramsey. On Hiawatha, there is no conflicting motive of concern. He simply set MnDOT priorites as he did, as a matter of judgment.

How do we cast ballots, based on his judgment?

Especially, if he hides from giving his rationales and justifications for setting his priorities for show over substance; and over safety. Risk aversion was not shown. That is obvious. If no suitable explanation is forthcoming, how do you vote?

Michele Bachmann is so egregious, it is easy to overlook almost anything in voting against her. Yet she has a large core of zealot and committed supporters.

Hence --- Back to square one.


Should Bob Olson be the candidate?


Who has the best shot at replacing Michele Bachmann, without a ton of baggage to haul around the campaign trail?

Who would be the best vote-getter in the Sixth District for the DFL Senate candidate?

Each of these is an open question.

Bill McCarthy cannot answer them for us. We must decide, as a matter of conscience. Not based on who Bill McCarthy or Betty McCollum says they like. That's hardly the criterion for good government - others say ...