Engineering quiz time....
#1
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Challenge yourself here:
A Backhoe weighing 8 tons is on top of a flatbed trailer and heading
east on Interstate 70 near Hays, Kansas. The extended shovel arm is
made of high tensile steel and the approaching overpass is made of
commercial-grade concrete, reinforced with 1 1/2 inch steel rebar spaced
at 6 inch intervals in a crisscross pattern layered at 1 foot vertical
spacing.
Solve: When the shovel arm hits the overpass, how fast do you have to
be going to slice the bridge in half? (Assume no effect for headwind
and no braking by the driver...)
Extra Credit: Solve for the time and distance required for the entire
rig to come to a complete stop after hitting the overpass at the speed
calculated above.
![](https://i44.photobucket.com/albums/f16/corvettecrazyjnk/pic20600_1.jpg)
![](https://i44.photobucket.com/albums/f16/corvettecrazyjnk/pic05249_1.jpg)
![](https://i44.photobucket.com/albums/f16/corvettecrazyjnk/pic16519_1.jpg)
I hope this isn't a repost.
A Backhoe weighing 8 tons is on top of a flatbed trailer and heading
east on Interstate 70 near Hays, Kansas. The extended shovel arm is
made of high tensile steel and the approaching overpass is made of
commercial-grade concrete, reinforced with 1 1/2 inch steel rebar spaced
at 6 inch intervals in a crisscross pattern layered at 1 foot vertical
spacing.
Solve: When the shovel arm hits the overpass, how fast do you have to
be going to slice the bridge in half? (Assume no effect for headwind
and no braking by the driver...)
Extra Credit: Solve for the time and distance required for the entire
rig to come to a complete stop after hitting the overpass at the speed
calculated above.
![](https://i44.photobucket.com/albums/f16/corvettecrazyjnk/pic20600_1.jpg)
![](https://i44.photobucket.com/albums/f16/corvettecrazyjnk/pic05249_1.jpg)
![](https://i44.photobucket.com/albums/f16/corvettecrazyjnk/pic16519_1.jpg)
I hope this isn't a repost.
#4
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Huh, I got these back on the 16th of February... evidently by a different camera earlier in that morning.
![](https://i19.photobucket.com/albums/b184/jwikoff99/HallStreetI-70Bridge005.jpg)
HallStreetI-70Bridge004.jpg
![](https://i19.photobucket.com/albums/b184/jwikoff99/HallStreetI-70Bridge003.jpg)
HallStreetI-70Bridge002.jpg
HallStreetI-70Bridge001.jpg
![](https://i19.photobucket.com/albums/b184/jwikoff99/HallStreetI-70Bridge005.jpg)
HallStreetI-70Bridge004.jpg
![](https://i19.photobucket.com/albums/b184/jwikoff99/HallStreetI-70Bridge003.jpg)
HallStreetI-70Bridge002.jpg
HallStreetI-70Bridge001.jpg
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Originally Posted by J Wikoff
Huh, I got these back on the 16th of February... evidently by a different camera earlier in that morning.
still amazing to see, IMO.
Just think if you were driving and that boom came flying out of the road in front of you OR hit the bottom of your car as you were on the bridge.
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Originally Posted by corvettecrazy
Just think if you were driving and that boom hit the bottom of your car as you were on the bridge.
![Evil or Very Mad](https://www.gmforum.com/gm/images/smilies/icon_evil.gif)
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Originally Posted by ga93sle
Originally Posted by corvettecrazy
Just think if you were driving and that boom hit the bottom of your car as you were on the bridge.
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Originally Posted by corvettecrazy
Originally Posted by ga93sle
Originally Posted by corvettecrazy
Just think if you were driving and that boom hit the bottom of your car as you were on the bridge.
![Evil or Very Mad](https://www.gmforum.com/gm/images/smilies/icon_evil.gif)
![Laughing](https://www.gmforum.com/gm/images/smilies/icon_lol.gif)
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Because the boom was not high enough when it first hit, but the angle that it sits at was still enough to carry it up and into the bridge. Look how flat that trailer is!!!
I've seen some similar things happen. Cars getting knocked off of a car hauler because the driver forgot to drop down the front car after the bottom was loaded! Trash haulers loading too high and having it spill out over the highway. But nothing that has caused that much damage!!!
I've seen some similar things happen. Cars getting knocked off of a car hauler because the driver forgot to drop down the front car after the bottom was loaded! Trash haulers loading too high and having it spill out over the highway. But nothing that has caused that much damage!!!