[TML] jump weapons

[Knapp]

On Wed, Aug 6, 2008 at 8:39 PM,  <shadow at shadowgard.com> wrote:
> On 5 Aug 2008 at 21:33, Knapp wrote:
>
>> > Barrington
>> > Nope.  Any engineer will tell you, you don't aim for absolute minimum.
>> > *Always* build in a safety margin.
>>
>> But is that not in part true because the Engineers never trust the
>> stats of the materials and the needs of the structure that were
>> calculated? If they KNEW everything they might build at the absolute
>> minimum but they don't.
>
> Nope. Because to build to the "absolute minimum" you *also* have to
> know everything about the conditions whatever you build will
> encounter.

Not that I disagree with what you are saying but, "nope", when I just
said they knew all the needs of the structure??

Also your examples don't show that over building works when the maker
then under builds it or as in many other case do things like not
tightening the bolts etc.

>
> Engineering "disasters" are as often a case of
> structures/vessels/whatever being subjected to conditions the
> engineers never expected as they are failure to design for expected
> stresses.
>
> And sometimes they are a case of folks making changes to the
> structure from what the designer specified without checking with the
> designer (that case of the hotel's internal walkways/"sky bridges"
> collapsing under the weight of a crowd was more due to the
> construction company chamnging the long support rods (which were
> supposed to be one continuous rod extending thru two or three stories
> into a couple of rods tied together at a plate. The *join* failed.
>
> Or in the case of a store collapsing (in Korea?) the somewhat
> adequately built store was set up for failure when it was decided to
> add another floor without making any changes to the existing
> floors...
>
> --
> Leonard Erickson (aka shadow)
> shadow at shadowgard dot com




-- 
Douglas E Knapp

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