😉
O wow!
Now I know!
🙂
That pretty well describes what goes on in strength of materials labs routinely. They break things to find out when and how they will fail.
Holy Cow, post: 354673, member: 50 wrote: That pretty well describes what goes on in strength of materials labs routinely. They break things to find out when and how they will fail.
Yep, back in the old college day's we used to "squash" all kind of stuff in the "Tinius Olsen" we weren't supposed to. Great fun!
B-)
Yup. Gotta understand how and why failure occurs at the most basic level in order to understand how to prevent it from occurring in real world applications. There are multiple potential types of failure. Which will happen first, thus being the most critical.
A prime example is found in the followup evaluations of what led to the deaths of so many in the hotel in Kansas City, Missouri back in 1981. 114 died and 216 more were injured in a matter of seconds. https://en.wikipedia.org/wiki/Hyatt_Regency_walkway_collapse
FL/GA PLS., post: 354683, member: 379 wrote: Yep, back in the old college day's we used to "squash" all kind of stuff in the "Tinius Olsen" we weren't supposed to. Great fun!
B-)
One professor I worked with started his introductory lecture in the materials testing lab with a warning to turn off cell phones. He then proceeded to display a phone he claimed to have confiscated in an earlier class. The phone quickly went into the compression test machine and was reduced to a paper thin wafer. He had very little problem with in class interruptions afterward.
When I was a kid there was an old timber bridge our school bus had to cross every day that was posted for "3 TONS MAXIMUM". The old school bus wasn't really much more than a 2 1/2 t. 1946 Chevy with long rails, but Mr. Ritchie would stop and make all us kids walk across the bridge. Then he would drive across and let us all get back in the bus.
If I remember there were probably a dozen kids at that point. Adults hardly weighed 100 pounds back then so us kids probably averaged 50 pounds apiece. At 12 kids, he was shedding maybe 600 pounds to get across the bridge.
But then again, in 1956 I don't guess it took an engineering degree to drive old number four.....
paden cash, post: 354717, member: 20 wrote: When I was a kid there was an old timber bridge our school bus had to cross every day that was posted for "3 TONS MAXIMUM". The old school bus wasn't really much more than a 2 1/2 t. 1946 Chevy with long rails, but Mr. Ritchie would stop and make all us kids walk across the bridge. Then he would drive across and let us all get back in the bus.
If I remember there were probably a dozen kids at that point. Adults hardly weighed 100 pounds back then so us kids probably averaged 50 pounds apiece. At 12 kids, he was shedding maybe 600 pounds to get across the bridge.
But then again, in 1956 I don't guess it took an engineering degree to drive old number four.....
Maybe he didn't trust the bridge and wanted you kids to be safe by walking across instead of risking being in the bus when it fell through.
Licensed Land Surveyor
Finger Lakes Region, Upstate New York
Holy Cow, post: 354710, member: 50 wrote: Yup. Gotta understand how and why failure occurs at the most basic level in order to understand how to prevent it from occurring in real world applications. There are multiple potential types of failure. Which will happen first, thus being the most critical.
A prime example is found in the followup evaluations of what led to the deaths of so many in the hotel in Kansas City, Missouri back in 1981. 114 died and 216 more were injured in a matter of seconds. https://en.wikipedia.org/wiki/Hyatt_Regency_walkway_collapse
Quite an interesting article, sad but true.
Thanks for the link. B-)
In Russia that's still how they test bridges, see the following:
http://englishrussia.com/2014/10/03/a-bridge-strength-test-25-loaded-kamaz-trucks/15/
FL/GA PLS., post: 354683, member: 379 wrote: Yep, back in the old college day's we used to "squash" all kind of stuff in the "Tinius Olsen" we weren't supposed to. Great fun!
B-)
When I was in college as a Civil Engineering major (before I discovered the joys of Land Surveying) I got to use this machine. I was lots of fun busting apart things!
I'm actually involved with a long-term survey of a historical bridge here in my hometown. It was built in 1906 and was the main bridge for the state highway up until a new bridge was built in the early 1990's. Last year we vacated the public right-of-way over the bridge (it went to a dead end cul-de-sac) and the land owner (a big company here) now uses it as their private entrance. They were concerned that during the construction going on the added traffic (that was within individual loading amounts) might cause the bridge to settle or shift. So we did weekly monitoring for the 3 months and now we are doing monthly monitoring for the next 2 years. We have affixed permanent targets to 5 spots along each side of the bridge and we use a reflectorless shot to a point on each target from the same control. I also have backup control points to verify with each setup. After each observation, I dump the points into a spreadsheet that keeps a running tally of the average coordinate (N,E,Z) over all of our surveys, calculates the standard deviation of this average, and displays how much the current position of each target varies from the average and from the previous.
So far, I have seen a net of zero movement in the bridge. We have a couple of hundredths here or there due to error in the instrument and such. But in the long term, that bridge hasn't moved at all since we started watching it.
NDrummond, post: 354802, member: 1865 wrote: In Russia that's still how they test bridges, see the following:
http://englishrussia.com/2014/10/03/a-bridge-strength-test-25-loaded-kamaz-trucks/15/
Thanks for that link, Nathaniel. I noticed too that they "Have a tradition of having the lead engineers go under it with a boat" while it was being load tested. We should REQUIRE that all the leaders in USA get the same health care..... nevermind!
And, I noticed, that the surveying equipment, was cobbled together.... Looked like an old Geodimeter tribrach in that mix.
Really cool pics.
N
