Woah, dude!
A pier sunk 3 feet? That ain't good!
Based on what I know about the geology of the area, I actually wouldn't expect most of the piers on this bridge to reach bedrock. I-43 spans the Fox River over a former estuary which itself sits over old lake beds. That means alternating layers of silt, sand, gravel and clay. It is likely a couple hundred feet to bedrock. Perhaps after a few decades of gradual settling through sand and gravel, the footing for this pier finally slipped into that clay layer?
It has me concerned that the entire span is in need of deeper pilings. Not sure what the retrofit for that would be. I have to assume the footings for the arch segment are much deeper than the approach spans (where this failure occurred). So perhaps the more expensive portion will be okay.
Pretty rotten timing though. With the soon-to-be I-41 expansion in full swing, the primary alternative for thru traffic is a little whack right now. Sucks for game days this season.
Superficially, especially from the prospective of the driver, this is similar to the problem the Hoan Bridge experienced in Milwaukee back in 2000. In that case, though, it was a cracked girder that caused the roadway (NB only) to sag. Similar location though; immediately adjacent to the main span. Unlike the Hoan, however, routine bridge inspections wouldn't pick up on something like this.
Even the bridges that aren't supposed to be in danger of falling down are in danger of falling down!
/sarcasm
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Topic: I-43 Fox River bridge in Green Bay, WI - repairs and restoration (Read 26088 times)