I-43 bridge in Green Bay closed

[Big John]

http://www.fox11online.com/news/local/green-bay/leo-frigo-bridge-closed-report-of-dip-in-the-road

Dip in the road.  Reminds me of a similar failure on the Hoan bridge in Milwaukee in 2000.  Where there were girder failures.

edit:  getting a report that it could be a column failure as some of the footings never did hit bedrock when they were driven.

[Big John]

Side view: https://www.facebook.com/photo.php?fbid=10151682765841295&set=a.205697631294.132544.70657021294&type=1&theater  Sorry it is a facebook page.

Column is sinking or swaying.

edit: No link but just was told that some of footings for the columns never hit bedrock like they should have.

[SteveG1988]

Is bedrock really hard to pile down to in that region?

[Big John]

Is bedrock really hard to pile down to in that region?

No.  But I suspect bad soil samples if they ordered pilings that were too short to reach the bedrock.



Fixed quote. - rmf67

[Alps]

More than that, if I were a DOT engineer and I heard the piles didn't hit bedrock, I'd tell them to stop and get longer piles before finishing the column.

[mgk920]

You also have to remember that there are some places where the bedrock is so far down that it is impractical to even try to reach it.  For example, this is the situation in the Louisiana Bayou area.  More locally, crews did not hit bedrock when building Miller Park in Milwaukee.

This is generally not a problem in NE Wisconsin and in fact, high bedrock is a problem in many areas around here such that crews sometimes have to go blasting to lay sewer and water mains, dig basements and highway cuts and so forth. But I'll wait and see what the guys at WisDOT find out before passing judgement on this part.

Mike

[Duke87]

You also have to remember that there are some places where the bedrock is so far down that it is impractical to even try to reach it.

Yes, but then you have to design for friction piles rather than end bearing piles. The latter is easy: hammer it in until you hit bedrock. For the former, you have to determine the appropriate length prior to driving and this depends not only on the load on it but also on the properties of the soil you're driving it through.

[Alps]

You also have to remember that there are some places where the bedrock is so far down that it is impractical to even try to reach it.

Yes, but then you have to design for friction piles rather than end bearing piles. The latter is easy: hammer it in until you hit bedrock. For the former, you have to determine the appropriate length prior to driving and this depends not only on the load on it but also on the properties of the soil you're driving it through.

Yeah, my context is "these piles are supposed to hit bedrock and they're not." You can't just say "close enough."

[triplemultiplex]

The bridge spans the mouth of the Fox River; it's an area that's a filled-in estuary.  The industrial area under the bridge originally looked like the marshy area around the 41-43 interchange.  Locally, it's going to be one of the deepest areas to bedrock.  There is also going to be significant clay layers as the lower Fox River was the location of a significant pro-glacial lake until the Green Bay lobe retreated north of Door County.  (Outlets for that lake formed the initial valleys for the Kewaunee and Ahnapee Rivers further east, incidentally.)

Get east and west of where this bridge is and bedrock would be quite shallow.  The Niagara Escarpment is the most significant geological feature in eastern Wisconsin, for example.

I'll be interested to see what role the underlying geology played in this problem and whether or not someone messed up three decades ago when it was built.

(There are currently two threads for this topic; one in bridges, one in the Midwest/Great Lakes forum.  Perhaps a merger is in order?)