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children ARE the future

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I think factors of safety in building codes should be based on weight of the
occupants. We can set 50 lbs for the standard. So most pre schools and
elementarty schools will have a importance factor = 1. Now my next house,
whenever I design it, will have a IF = 5, since I tip the scales at about
250lbs (I'm big boned). High schools will be equal to about 3. Hospitals are
full of sick, skinny people, back down to a 2.5. A jenny craig or place like
that, your guess is as good as mine.

BUT, if your kids go to a preschool or other school with less then 250 rug
rats, then your kids are no more important then your local felons, according
to code (jails and detention facilities). I guess the danger with a jail is
if the structure fails then the inmates could escape. But I think barbed
wire and chain link fences would behave well in a seismic or wind event. To
me, the jails themselves should be built with a normal importance factor,
but those guard towers where the guys stand with machine guns should have
HUGE importance factors.

Now if you are in college, then I guess you aren't all that important unless
there are at least 500 of you. If it is any other structure, not that
important until there is at least 5000 people.

I hope the sarcasm is apparent by now. My actual point is this, all of these
criteria seem to have been determined by government or insurance officials,
who want to pay the least amount of premiums in the event of a disaster, and
have the smallest body count to explain to the public. They also seem to
revolve around socio-economic factors, which include who occupies the
structure, how many, and how long the occupants and buildings will be there.
Also, the importance to society if that building was not operable. Your
local supermarket is thus not as important as a hospital or a school with
2000 kids. All of the other things others have mentioned make sense as well.

But shouldn't all the buildings we are designing, per code, withstand the
worse case loading events? So is the Iw just an additional factor of safety
based on the sheer number of occupants? Is it to prevent damage that may
impair the useage of the structure, even though it did not fail?

Great question you posed Eric, and good responses.

Andrew D. Kester

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