Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: We're Not Getting Older, We're Getting DUMBER [WAS: Any Young Engineers Out There?]

[Subject Prev][Subject Next][Thread Prev][Thread Next]
One of the scariest things I recall is after a big convention center collapsed (McCormick in Chicago maybe) they looked back at the photos of the building being erected 20+/- years earlier and saw that the steel upper chords of the 3-D trusses were already starting to buckle because they hadn't been braced adequately ... but no one noticed.
Ralph

In a message dated 1/30/06 7:11:37 PM, chrisw(--nospam--at)skypoint.com writes:
On Jan 30, 2006, at 5:17 PM, S. Gordin wrote:
> But weren't the structures affected/damaged by the Loma
> Prieta earthquake mostly designed to much earlier codes?  By the same
> token, many similar structures - again, designed by earlier codes, had
> successfully survived.
I've heard that the problem wasn't the structures so much as with the
connections and the porblmes with the connections seemed to be weld
ductility or weld quality issues. And before you start talking
successful survival you need to know how different the design loading
was from the actual loading. Mother nature does what she does and
doesn't give a damn what we engineers assume for loading or probability
or confidence level. All the whining we hear from people who have 'done
it that way and never had a problem,' ignores the issue of whether the
detail that gave no problem ever saw the design load. I'm sure there
are engineers poking through the ruins of that Polish convention hall
who are thinking to themselves, 'Boy, we always did it that way and
never had a problem,' along with some colleagues thinking to
themselves, 'God dammit, I've been nagging about design snow loads for
20 years, and no one believed me.'
Christopher Wright P.E. |"They couldn't hit an elephant at
chrisw(--nospam--at)skypoint.com   | this distance" (last words of Gen.
.......................................| John Sedgwick, Spotsylvania
1864)
http://www.skypoint.com/~chrisw/