On Wednesday 04 February 2009 14:54:24 Howard Ressel wrote:
> This was a bit back but i received a response from a structural engineer
> friend of mine and he tends to agree.
> --
>
> "Go for a Metric America"
> Howard Ressel
> Project Design Engineer, Region 4
> (585) 272-3372
>
>
>
>
> I would agree that designing steel in metric is not as user friendly.
> The steel section properties are typically mm2, mm3 or mm4 and are
> very
> large numbers.  For example the area of a W36x230 beam shape is 68 in2
> or 43600 mm2.  Similarly, the bending section modulus is 837 in3 or
> 13700000 mm3.  The larger values are not that easy to work with.

For the bending section modulus, we can say it's 13.7 liters, even though it's 
not a volume. The second moment of area is on the order of millions of 
quartic millimeters, and since there's a 10^12 ratio between the quartic 
millimeter and the quartic meter and powers of 10 that aren't powers of 1000 
are avoided, the numbers are unwieldy. I think the solution is to give a name 
to the quartic meter, even though I know of no other use for it, so that the 
prefix "micro" can be attached to it.

Pierre

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