Is there a Civil Engineer in the house?

[RONALD]

Yesterday a busy bridge approach over the Chicago River, on Lake Shore Drive, started to shear apart in two girders. Traffic is stopped in all the northbound lanes, until they can build a temporary structure to support it directly under the two shear cracks of the two girders.

My problem, is why wasn't the concrete pier placed under all those joints when the bridge was built?

That joint as built was in shear, if the pier had been under the joints the joints would have been in compression, and not have failed.

So, this is in the province of Civil Engineering; anybody out there?

[NP317]

Holy Moly! That bridge support design looks SO wrong!
Perhaps designed by an UNcivil engineer?

Maybe a construction error, and someone said:
"Oh, it will be OK..."
Yea. For a while.

Keep us posted on resolution, please.
~RN

[SteveHGraham]

The construction companies belonged to two different Mafia families, and they didn't communicate well. The concrete is also problematic because it's full of dead guys named Vinnie.

[SteveHGraham]

Also, your video is taking forever to load.

[RONALD]

Here are a lot more details:

https://www.google.com/search?source=hp ... m1XViN48Ns

Because I drive a pickup truck,(supposedly cars only) and live ~ 45 miles to the northwest, it's been decades that I drove on that road.

The first photo is not a video, but a screen capture.

[SteveHGraham]

You murdered my joke.

[John Hasler]

The construction companies belonged to two different Mafia families, and they didn't communicate well. The concrete is also problematic because it's full of dead guys named Vinnie.

Mob, not Mafia. It's in Chicago.

Plausible explanation: Due to some oversight such as a failure to read some Federal regulation closely enough it was discovered after the steel had been ordered that the pier spacing had to be slightly wider than had been planned. Then someone who should not have signed off on the change order.

[Edit] Here's a document on girder splicing: https://www.fhwa.dot.gov/bridge/steel/p ... lume14.pdf

The splices in that photo look wierd to me (but I'm not a CE).

[SteveHGraham]

The urge to "correct" people on the Internet is an amazing thing. I shouldn't take the bait, but the "mob" is, in fact, part of the Mafia, as various sites will tell you, and it is also referred to as "the Outfit."

I feel like I'm doing standup in front of Dustin Hoffman in Rain Man. I can't remember the last time I regretted making a joke this much.

Next someone will claim that biscuity glop they serve in Chicago is pizza.

[earlgo]

I am not a CE either.
But, every bridge that I have looked at has had some kind of expansion joint OVER a pier and sitting on a roller or rocking pad. Mr. Hasler is most likely correct that the pier is in the wrong place or the girders were cut wrong, or worse, installed in the wrong spot. That would mean there is another joint not in the right location. WoHoo!

Reminds me of the recent debacle in Akron, OH.https://fox8.com/2018/12/03/semi-carryi ... 77-closed/

--earlgo

[SteveHGraham]

Maybe lawyers sneaked onto the site at night and moved the pillar.

[John Hasler]

Organized crime not really being very well organized being pedantic about such regional slang as "The Outfit" or "The Mob" is a joke. Which is how I intended my remark.

> Next someone will claim that biscuity glop they serve in Chicago is pizza.

Won't be me. Open-face pot pie.

[SteveHGraham]

Maybe we just shouldn't joke. Maybe there is some kind of remedial humor class.