Is there a Civil Engineer in the house?

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STRR
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Re: Is there a Civil Engineer in the house?

Post by STRR »

While I'm not a CE, I have been part of many bridge builds. This is a fairly common joint. The first problem to solve is how to allow expansion without the bridge moving ON the piers. Thus, the off-pier expansion joint. The joint, pictured, allows for sliding action of the section to the right of the photo. These joints may have been used for each section of this bridge. Without more photos, it is uncertain.

Several things have to be addressed here. How OLD is the bridge? Has it outlived it's planned life span? Has it been maintained properly, i.e. painted and inspected? Many of the bridges in use today are long past expected/planned lifetime. The old adage of If it isn't broke don't fix it really applies to highway infrastructure. Very expensive, time-consuming, and extremely inconvenient. So, this type of thing has to happen before the bridge gets replaced.

It is so easy to blame the designer, engineer, construction people when problems show up. Are they to blame or is it the administration who ignores warnings and limits? I can guarantee you will never hear a politician confess he knew about the problem but did nothing to address it. Much easier to get funding when there is a problem that it is to prevent a problem.

An investigation most likely will/would show this problem has been developing for a long time. This is just the conclusion. Has anybody asked for the inspection records? Standard, required, inspections are designed to find signs of this type of problem long before it becomes a problem.

Good thing someone saw it before it failed completely.

Good Luck,
Terry
SteveM
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Re: Is there a Civil Engineer in the house?

Post by SteveM »

The Mianus River bridge on 95 in Greenwich fell in because it had pin and hanger construction and was neglected for a long time. The bridge over the harbor in Bridgeport (yes, where they made the machines) had the same construction at the time and you could just see the rust all around the pins.

To make things worse in Greenwich, the highway crossed the river at an angle making the bridge deck pieces parallelogram shaped, which introduced a twisting action that certainly wasn't good for longevity.
920x920.jpg
The politics of it are that the person who votes to properly fund maintenance will probably get pilloried for spending, but the one that lets everything go to pot will be out of office before anything happens.

Steve
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mcostello
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Re: Is there a Civil Engineer in the house?

Post by mcostello »

Would the Mob hire out the job to the Chinese? :)
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NP317
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Re: Is there a Civil Engineer in the house?

Post by NP317 »

Steve: I got your first joke.

You'd still be welcome at our Thanksgiving dinner.
I'd just have to explain why I invited a Floridian...
~RN
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ctwo
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Re: Is there a Civil Engineer in the house?

Post by ctwo »

I suspect that the left side of the span is anchored to the pillar and the right side is designed to float and that is probably an expansion joint.

oh, what STRR said...
Standards are so important that everyone must have their own...
To measure is to know - Lord Kelvin
Disclaimer: I'm just a guy with a few machines...
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warmstrong1955
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Re: Is there a Civil Engineer in the house?

Post by warmstrong1955 »

Sounds like they are blaming it on corrosion, but one has to question the inspections & inspectors.
A lot.

In February of 2017, a dam failed in Montello NV. It had passed inspection the previous June.
I never heard much more about that, but it makes ya go mmmmmmmmmmm...........
Today's solutions are tomorrow's problems.
SteveM
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Re: Is there a Civil Engineer in the house?

Post by SteveM »

warmstrong1955 wrote: Wed Feb 13, 2019 2:28 pm Sounds like they are blaming it on corrosion, but one has to question the inspections & inspectors.
Corrosion.

One of the reasons we have inspections.

Steve
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warmstrong1955
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Re: Is there a Civil Engineer in the house?

Post by warmstrong1955 »

SteveM wrote: Wed Feb 13, 2019 2:34 pm
warmstrong1955 wrote: Wed Feb 13, 2019 2:28 pm Sounds like they are blaming it on corrosion, but one has to question the inspections & inspectors.
Corrosion.

One of the reasons we have inspections.

Steve
My thought as well.
And being as how that expansion joint is the weakest link in those I-beams.....

Bill
Today's solutions are tomorrow's problems.
SteveM
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Re: Is there a Civil Engineer in the house?

Post by SteveM »

warmstrong1955 wrote: Wed Feb 13, 2019 2:43 pm And being as how that expansion joint is the weakest link in those I-beams.....
Yea, it's not like we don't have any idea WHERE to focus an inspection.

Steve
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