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Re: deck collapse, part IX

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I just tend to look at it from the perspective that I am sure that if YOU
were the one of people involved in the situation that you would not like
people concluding that you are "sleazy" or reffered to in other
disparaging ways without more information (if not all) being available.  I
know I wouldn't like it if I were in that situation.

Not to mention that in today's world of sue first, ask questions later,
careless comments or opinions could cause you to be on the end of a
slander lawsuit or some such. :-)

It just bothers me to see the jump to conclude guilt when supposely one of
our "prime directives" in our way of life is innocent until proven guilty.
At the risk of making a political statement...this mentality seems to be
more prevelent since recent events (i.e. 9/11) and to me it goes against
what I consider one of the core values/rights that makes this country
great.  While technically such a right is not afforded to non-US citizens,
but if we purport to be in favor of such rights and that we are the "best"
then I would think that we would be willing to treat non-US citizens in
the same manner.  I guess I am just rather naive.

HTH,

Scott
Ypsilanti, MI

On Thu, 3 Jul 2003, Andrew Kester wrote:

> How did I know two sentences in to your response it was you Scott? You have
> quite the distinctive style. Also when I know I cannot see your name without
> scrolling down it must be you. Have you been on vacation? Perhaps a canoe
> trip on a lovely Michigan river? If your engineering and teaching career
> ever get boring there is definitely law school or politics. Just joking,
> mostly :)
>
> I think I may have been misunderstood, but I was basically assuming an
> engineer was not at fault in the design. That may be jumping the gun,
> because you brought up lateral loading, or sway bracing. Although even
> without diagonal braces, a deck is usually braced through diaphragm action
> via the deck to the ledger, and the stair, but this is one possibility. But
> it seemed the mode of failure was not through what you would expect from
> sway, it was more of a vertical, "pancake" type collapse. I still contend
> there is no big hurry in getting such a disaster immediately cleaned up. I
> would think you would want at least a few engineers each investigating, so
> you get different opinions. It is hard to pick a failed connection out of a
> pile of rubble. I am sure we have all done a bit of forensic or diagnostic
> engineering, and that is usually the most difficult. I have never done
> anything on a full scale collapse where all you are left with is a pile of
> rubble, that has to be very difficult to figure out.
>
> But you have a point Scott, we should not jump to conclusions. It is a
> little sad about WTC victims' families not understanding the collapse being
> cleaned up. It doesn't take a structural engineer to figure out that we do
> not normally design buildings for jet airliner impact. Nor do the MEP guys
> design sprinklers and ventilation systems for large amounts of jet fuel.
> Think of how many lives would have been saved if all of the towers would
> have been immediately evacuated. ( I don't know if the answer is airport
> security, but it seems more logical then designing every building to be
> jetliner proof.)
>
> I think it must be a sign, but I am sitting down late last night for some
> dinner and flipping through the TV I find ENGINEERING DISASTERS on History
> Channel. (Timely scheduling?)  This is part of a series, so check your local
> listings, it is GOOD. Also makes you a little uneasy as an engineer.
>
> Mainly civil/structural failures, but also electrical and mechanical. THere
> was a dam north of LA that originally supplied LA with water, which the day
> after being inspected by the "architect/designer/builder" (this is in the
> 20s), who gave it a clean bill of health, collapsed killing 400+ people. The
> guy lived the rest of his life in remorse and in recluse.
>
> The lift slab technique of building slabs on the ground and jacking them up
> into place- that led to a pancake type failure during construction in CT ,
> killing 30+ workers. I think that was the worse single construction disaster
> in US history. CT banned this type of construction and everyone else pretty
> much dropped it. THere was a huge pile of rubble to sift through. Turns out
> a small steel wedge slipped loose that held the slab to the jack. That just
> shows you how one tiny detail can cause the whole structure to fail. One
> little hanger connection could have failed the whole deck....
>
> I may have mentioned this on the list already, but I highly reccomend the
> book, "Why Buildings Fall Down". It actually highlights a lot of the
> disasters on this show. It even discusses the aeronautical structural
> failures of the first jetliners, the British Comet. It relates to us because
> it is a material fatigue stress failure at a window, a natural weak spot on
> any structure. Anyway, this book is light and easy reading for a structural
> engineer as it is written for the lay person. Good reading for a friend or
> family member who wonders what we do all day. (My dad actually bought it for
> me. I have passed it to the other SE in the office and he really enjoyed it
> too.) Since most of the structures discussed in the book were a bit more
> then I will ever design (bridges, dams , stadiums), it was a good learning
> experience for me. The main thing you learn is it is all about HUMAN ERROR.
> Whether from a load perspective, code enforcement, miscalculation, poor
> coordination, using unproven or the wrong materials, poor maintenance and
> inspection, or poor construction, it does not matter how many computers we
> have, it is still up to us. Also, connections and redundancy!!
>
> (Then I also saw a special about Rome the other night and they showed a
> stone bridge they built that is still being used- not just standing. They
> did not pay the builder for 40 years to gurantee it had been done correctly.
> Do you think the Romans had STAAD or AASHTO guidelines? They did not have
> the wheelbarrow, compass, or level.)
>
> Well, I guess that is enough speculation, and like Scott smartly suggests,
> sit and wait for all the info. I will still bet someone it is a connection
> failure...
>
>
> I hope everyone has a safe 4th, keep the number of people on decks low, and
> stay away from large trucks of fireworks (4 people died down here in FL
> yesterday).
>
> Andrew Kester, EI
> Longwood, FL
>
>
>
>
>
>
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