Alex, I'll take "new math" for $500...
Posted on 07/19/2018 10:59:51 PM PDT by Tolerance Sucks Rocks
Hope it’s better than the one at FIU.
Looks like the leaf spring stack on my truck.
They normally have an Achilles heel though: fire. Heat will usually weaken the composite quickly, unless it's a special epoxy and fiber material heat-cured at high temperature. But then your cost will go way, way up. Maybe they have a solution.
I wonder if the sun will accelerate or pull (dry out) epoxy/base liquid used to hold the mix together . I didn’t see in the article where the girders were weather tested (but they must have)
Sun. That was my first thought.
Well building it in 72 hours is a great thing but EPA permits will take 6 months.
“..but EPA permits will take 6 months.” Scratch that, 6 years.
Where are you seeing this?
A drawing would be helpful. The photo is not.
I’m the project manager on a small bridge that crosses a non-fish bearing irrigation return drain. It’s taken over 3 years from initial funding through permitting to be approved for construction. Our issue now is the final permits were issued in June but our designated in-water fish window is between July and August and the bid processes takes 2 months, so we won’t be building this year.
Now were trying to negotiate a “floating” fish window that would allow us to bid and build based upon our bridge delivery schedule. It takes about 4 months after bid award to receive the manufactured girders, otherwise we have to wait until next July...
How often do bridges catch fire?
It's not that it happens too often, but you have to consider the consequences and expense if and when it does.
That sure went down the memory hole, huh. Lots of articles that first week, and absolutely nothing since.
Are you looking at the yellow slabs near the top of the picture? Everybody in the picture is looking toward the left.
Composites don’t do well with impact damage, especially if the fibers crack.
One would hope. But, never assume.
Alex, I'll take "new math" for $500...
Bump
It's 110° today where I live. Was my first thought as well. Also, the quote from one of the engineers "Today's bridge test exceeded our expectations." was somewhat disquieting. I would think they'd have dialed in their expectations pretty close to reality, as we have a pretty good handle these days on material sciences for the most part.
The careful text books measure
(Let all who build beware!)
The load, the shock, the pressure
Material can bear.
So when the buckled girder
Lets down the grinding span,
The blame of loss or murder,
Is laid upon the man!
Not on the stuff-the man!
-The Hymn of the Breaking Strain by Rudyard Kipling
That's one. Cost is another.
Cheap, high quality, fast - pick two at most.
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