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RE: More Canada ???

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Sounds like a short list of reasons we invariably push back against converting 
 to SI.

Personally, I don't give a rat's furry rump either way. I just wish we'd 
fish or cut bait.

In 1996, my employer at the time prepared a large set of highway plans for 
a Texas DOT project in the Rio Grande Valley. TxDOT had decided to get ahead 
 of the curve since the Federal DOT had mandated switching to SI for future 
 projects, and this was one of the first jobs under the new SI standards.

As we were completing that project, Congress put everything off indefinitely 
 for the mandatory conversion. (Interestingly, the contractor on our highway 
 project had an entire office trailer full of junior engineers whose task 
was to go through our plans and convert everything to feet, inches, pounds, 
cubic yards, etc. so their predominately Mexican workforce could use them).

In TxDOT's case, they had spent untold thousands of publicly-funded manhours 
 coming up with brand new specs and standards. Since they were going to all 
 that trouble they decided to take the opportunity to completely revamp their 
 entire body of standard documents so it wasn't simply a conversion to SI, 
but an addition of new standards and a major revamp of old standards.

When they pulled the plug on SI conversion, TxDOT had to spend another few 
thousand manhours taking the SI versions they'd just published and converting 
 THEM to Imperial units!


-----Original Message-----
From: seaint-seaosc(--nospam--at) [mailto:seaint-seaosc(--nospam--at)] On 
Behalf Of Paul Ransom Sent: Wednesday, April 16, 2014 8:11 AM
To: seaint-seaosc(--nospam--at)
Subject: Re: [SEAINT-SEAOSC] More Canada ???


We don’t use the AISC conversions to SI. We tend to be more liberal in our 
 Imperial-SI conversions. The design standards are calibrated to the metric 
 calculations but are frequently dimensionally non-specific (e.g. use 
consistent dimensions and you get appropriate results).

So, W6x15 = W150x22

Fy = 50 ksi = 350 MPa (vs 345 MPa per AISC)

We still do projects in either system. Bolts are usually spec’d as imperial 
 size but occasionally I see M20 instead of ¾” on an SI project.

CISC provides a cross-reference table of sections in the Handbook of Steel 

They also have a spreadsheet that is available with all section properties 
in metric.

Truncated 304 characters in the previous message to save energy.

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