Big Boo-Boo on 950 tons of bridge

It was a federal TIGER project, part of Obama's stimulus. And took five years--same as the Empire State Building--to build.

It's an unintended monument to all sorts of things.

(*) Targeted Investment Generating Economic Recovery

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About TIGER Grants

The Transportation Investment Generating Economic Recovery, or TIGER Discretionary Grant program, provides a unique opportunity for the DOT to invest in [...] Since 2009, Congress has dedicated over $5.6 billion for nine rounds of TIGER to fund projects that have a significant impact on the Nation, a region or a metropolitan area.

Cheers, James Arthur

Reply to
dagmargoodboat
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$5.6B is a pittance. The real story is all those goddammed administrative b ureaucrats, you know the people whose full time job is attending meetings, writing incoherent summaries of those meetings, and then summarizing the su mmaries on a quarterly basis even more incoherently. In their world, the te chnical workforce, the people who design and actually construct the bridge, are "a dime a dozen" and have little significance relative to the adminstr ative staff.

Reply to
bloggs.fredbloggs.fred

or it was installed wrong,

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Reply to
Lasse Langwadt Christensen

FWIG, not only was it a TIGER grant but it's a research project run by the engineering department FOR PROFIT. I wonder if the patent royalties are going to cover the liability.

Reply to
krw

Oink.

--

John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com
Reply to
John Larkin

Oink oink!

I was wrong about the Empire State Building. Wiki says the ESB was built and open in just under 14 months.

Cheers, James

Reply to
dagmargoodboat

On Monday, March 19, 2018 at 2:01:31 PM UTC-4, snipped-for-privacy@gmail.com wro te:

:
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bureaucrats, you know the people whose full time job is attending meetings , writing incoherent summaries of those meetings, and then summarizing the summaries on a quarterly basis even more incoherently. In their world, the technical workforce, the people who design and actually construct the bridg e, are "a dime a dozen" and have little significance relative to the admins trative staff.

All true.

My brother did time as one of the administrative wonks at an aerospace plant. The administrators referred to engineers as "desks," and tried, in their bureaucratic wisdom, to estimate how many "desks" each job would require. Or, alternatively, how many additional "desks" would be needed to finish an existing job in half the time, etc.

Cheers, James Arthur

Reply to
dagmargoodboat

On Tuesday, March 20, 2018 at 12:04:50 PM UTC+11, snipped-for-privacy@yahoo.com wrot e:

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ve bureaucrats, you know the people whose full time job is attending meetin gs, writing incoherent summaries of those meetings, and then summarizing th e summaries on a quarterly basis even more incoherently. In their world, th e technical workforce, the people who design and actually construct the bri dge, are "a dime a dozen" and have little significance relative to the admi nstrative staff.

Whence the British joke about the manager who - when told that it took one women nine months to produce a child - assembled a team of nine women to pr oduce one in a month.

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Project management is an inexact science, and nobody involved in it serious ly sees it as capable of providing reliable predictions. Some plan is bette r than no plan, and you can see potential bottle necks early enough to do s omething about them if you do look ahead.

Administrators who thinks that they can do better are deluding themselves, but self-delusion is a fairly common problem - you think you know what is w rong with socialism, but have yet to work out how it differs from communism .

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Bill Sloman, Sydney
Reply to
bill.sloman

It looks like a spaceframe bridge, why would it need stays?

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This email has not been checked by half-arsed antivirus software
Reply to
Jasen Betts

usly sees it as capable of providing reliable predictions. Some plan is bet ter than no plan, and you can see potential bottle necks early enough to do something about them if you do look ahead.

, but self-delusion is a fairly common problem - you think you know what is wrong with socialism, but have yet to work out how it differs from communi sm.

PERT

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Dan

Reply to
dcaster

To keep the concrete base in compression. Usually you pre-stress the concrete with giant bolts.

Cheers

Phil Hobbs

Reply to
pcdhobbs

iously sees it as capable of providing reliable predictions. Some plan is b etter than no plan, and you can see potential bottle necks early enough to do something about them if you do look ahead.

es, but self-delusion is a fairly common problem - you think you know what is wrong with socialism, but have yet to work out how it differs from commu nism.

Garbage in, garbage out.

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They are a great way of displaying guesswork, but they rarely capture the r eal complexity of what is going on, or at least not in projects that involv e real development, as opposed to generating more of the same with a differ ent paint-job.

Been there, put up with that.

--
Bill Sloman, Sydney
Reply to
bill.sloman

And it looks like one of those giant bolts failing may have initiated the collapse.

In this video, starting at 0:15 on the right side, you can see a critical tensioning bolt hanging way out from a rectangular concrete block on the upper deck. It looks like a tank's gun cantilevering out of a (concrete) turret.

The workers then walk up onto top deck and at 0:22 the leading worker puts his hand on the bolt.

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Crowd-sourced ME's are suggesting the fact that the bolt was ejected rather than pinched and trapped by the collapsed structure suggests the bolt failed first and, like a broken rubber band, was slingshot-ed out of its channel.

Cheers, James Arthur

Reply to
dagmargoodboat

I think the bolts are put in tension before the concrete is poured. This way the concrete grips the bolt along the entire length so it cannot come loose.

My apartment has floors of prestressed concrete beams 10.25" thick and 4ft wide. They extend from one side of the building to the other.

The concrete beams make living in the building much nicer than with wood floors. There are no creaks or shakes as people walk across the floor. The building feels extremely solid, which it is. The only problem is in the winter when if gets down to -30c at night. The building shrinks, and it makes a loud bang as the tension is taken up by the floor.

There are safety concerns. Concrete doesn't deteoriate like wood. It doesn't burn. Walls are not load-bearing, and in my building the studs are steel instead of wood. All these factors make the building essentially fireproof, and I feel safer living here than in any other building I have seen.

The only downside I can see is the floors have a slight arch. Perhaps 2 inches higher in the middle than at the ends. Thie may not seem like much, but it definitely affects planning for shelves. Also, it is virtually impossible to weatherstrip the doors. The distance between the floor and the bottom of the door changes as the door is opened. I could find nothing in the hardware stores that could accommodate such a variation. The solution was to take a 5/8" plastic vinyl angle strip and glue it to the floor, butting up against the door.

It turns out that hot glue will not survive repeated kicks from shoes, but Amazing Goop Marine Grade does an excellent job. It glues to the vinyl and the ceramic floor just fine. The only thing you have to do is clean both with methyl hydrate, or methanol. Available in any hardware store, very inexpensive. A 50-50 combination of methanol and 70% isoprop will clean fingerprints off fridge door handles like nothing else I've seen. But don't use it on door frames. It will remove the paint along with the dirt.

Reply to
Steve Wilson

The bolts on this bridge were adjustable, and were being adjusted when the structure failed.

CNN has a particularly good picture of the failed bolt at the top of their article, here:

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Cheers, James Arthur

Reply to
dagmargoodboat

real complexity of what is going on, or at least not in projects that invo lve real development, as opposed to generating more of the same with a diff erent paint-job.

Just because you have not seen effective program management does not mean t here is no effective program management. Have you ever worked on a program involving multiple prime contractors and many more sub contractors. Say o n the order of the Saturn V program ?

Dan

Reply to
dcaster

This was a post-tension design. I think they used hydraulic jacks to tension the cables or rods after the concrete was poured.

Apparently the crew was tightening tension cables when the bridge collapsed. Possibly too much, or too little, tension.

Doing that over an active roadway was imprudnet.

--

John Larkin         Highland Technology, Inc 

lunatic fringe electronics
Reply to
John Larkin

The entire design was political. It was a showpiece for a government program and an architecture project. 950 tons of footbridge folly.

When I was in engineering school, we made fun of the architects. They couldn't design stuff that stood up.

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John Larkin         Highland Technology, Inc 

lunatic fringe electronics
Reply to
John Larkin

Amazing. A collectivist (socialist/communist/central planner) who doesn't believe programs can be managed There's one for the books.

Reply to
krw

The question that struck me was why all the concrete in the first place?

The 60 Freeway here in Tempe, AZ, near the ASU campus, has several pedestrian bridges... some spanning as many as _12_ lanes... not a one is concrete. ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
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| STV, Queen Creek, AZ 85142    Skype: skypeanalog |             | 
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  | 
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Reply to
Jim Thompson

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