Skip to comments.Breaking: Bridge Collapse in Minneapolis
Posted on 08/01/2007 4:28:27 PM PDT by ButThreeLeftsDo
Just turned on the news. 35W bridge collapsed in the Mississippi River. Cars, trucks, semis.....
Fires burning, tanker trucks, at least one school bus, more than ten cars......
Just now breaking.......
Nix on the “reckon”, too. That would be more Southern. :^D
Somewhat disagree. Every bridge I am aware of (I used to inspect them and supervised other inspectors afterward) has bad expansion joints. Every one of them is rusted and most are totally locked up. It sometimes causes localized failures, particularly on the deck if it is concrete, however, I have never heard of that being a primary cause of failure.
My bet is a fatigue crack that was hidden or missed during inspection. The combination of bumper-to-bumper traffic and the construction machinery was more than the remaining tension (the uncracked area) could take.
I agree. I have seen a lot of fatigue failures (most not on bridges, thankfully), and every one of them has been in a tension member or in a tension area.
I have never seen a fatigue failure in a compression member. I have seen buckling in compression and seen all kinds of different joint failures (weld cracks, poor fusion, rivet shear, bolt shear — but more often shear failure in the plate the rivet or bolt goes through — bad metal, bad repairs, bad initial welding, but I have never seen a fatigue failure in compression.
Frighteningly, I live in the land of PennDOT.
My understanding was it is a riveted connection not bolted..but nonetheless, something failed.
there is a good diagram.
The center span over water is 468’ (if I recall correctly) of the 1900’ total.
The whole bridge was limited to one lane each direction where there is normally four lanes of heavy traffic each direction.
Cannot find links to a terrific TV documentary on The World’s most celebrated bridges - but did find this interesting site.
Has that been confirmed? Even 2 days later i've heard conflicting accounts, 1/2 those saying 2 lanes were open per direction (4 total), and the other half saying only 1 lane per side(2 total). Could it be the reason for the confusion was that while parts of the collapsed section was down to 2 lanes, others were still at 4?
Actually the bridge next to it is the 3rd avenue bridge. Not a freeway.
The 35W bridge carried traffic in both directions.
Very interesting analysis. Thank you.
Great pics with notes. Thanks.
There were two lanes going in both directions. It would be quite rare for a major freeway to be down to one lane only in each direction during rush hour. (Sometimes they do it on the weekends.)
Road or bridge construction control varies hour by hour, I would think - and at Rush Hour usually they make necessary adjustments. Probably not a conflict - just a time difference.
OK, thanks for the information. It helps to know the facts.
Thanks for the information.
“They can have my 1978 Camaro when they pry it from my cold dead hands....”
There will allways be gas for those willing to pay for it - but the more people taking light rail, and driving the ity-bitty electric cars, the more gas left at a more reasonable price for you.
Actually I made a mistake. It’s the 10th avenue bridge.
The 3rd avenue bridge is on the other side of the stone arch bridge. :)
Interesting article here about the inspections and decisions made:
“According to a source with knowledge of the state and federal investigations, MnDOT is focused on the east side of the northbound section of the bridge past the Washington Avenue entrance as the likely spot where the bridge first gave way.”
You make several very good points.
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