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RE: Steel beam from 1913

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I'm just curious.

I'm not exactly sure why the designation of a beam that old matters.

When you are designing a system, you do so with prospective materials, 
things that don't even exist yet in their final form. Therefore, it makes 
sense to design using standard size designations, etc.

But when something is in situ - especially if it has been there as long as 
this - the original design assumptions have little relevance if any.

When I look at a project like that, I don't really care what the designated 
 size was, that someone used. I care only about what's there.

Fortunately in a case like this where you are accessing the in situ system, 
 you have merely to take measurements. You can and should take into account 
 ACTUAL lengths, thicknesses, etc, rather than what was originally assumed 
in the design.

And that information will include such things as how much of what was put 
there, is still there, e.g. degradation such as rusting away. It might even 
 be necessary to perform mechanical testing on coupons taken from the 
system if conservative assumptions can't be reliable.

It is easy enough, when you're dealing with familiar shapes like H-shaped 
beams, to compute the geometric parameters such as moment of inertia, from 
the dimensions. I have software that can do that in minutes.

It seems like we are used to thinking of design, as distinct from analysis, 
 when we investigate in situ structural systems.

They aren't the same thing, except as an adjunct to design of repairs or 
alterations.

Regards,

Bill Polhemus

-----Original Message-----
From: seaint-seaosc(--nospam--at)mail-list.com [mailto:seaint-seaosc(--nospam--at)mail-list.com] On 
Behalf Of Nick Fanger Sent: Tuesday, June 25, 2013 7:00 PM
To: seaint-seaosc(--nospam--at)mail-list.com
Subject: RE: [SEAINT-SEAOSC] Steel beam from 1913

B20

Weight: 56 plf
Depth: 19 - 7/8"
Width: 8"
Flange thickness: .425"

>From Bethlehem Structural Shapes Catalogue S-27 (1928)

Email me directly for a pdf of the catalogue.
nick(--nospam--at)kishrigging.com

I also have the Beth from 1948, and the Carnegie Steel Company pocket 
companion from 1903 and 1923.

Nick Fanger, SE

-----Original Message-----
From: seaint-seaosc(--nospam--at)mail-list.com [mailto:seaint-seaosc(--nospam--at)mail-list.com] On 
Behalf Of Valerie Eskelsen Sent: Tuesday, June 25, 2013 3:35 PM To:

Truncated 616 characters in the previous message to save energy.

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