Fabrications Errors? 1

[abusementpark]

How does AISC address fabrication errors? Is there anything specific that structural engineers need to consider with regard to fabrication errors?

It seems to me that you would only know about a fabrication error if it were large enough to require some sort of retrofit or solution requiring the EOR's input.

 

[enginerding]

Read the AISC Code of Standard Practice. All sorts of tolerances are provided (so you know if it really is an error), as well as arbitration inspections. It's a free download for members. Otherwise it's in the back of the steel manual.

 

[Den32]

Yes, check out

http://www.aisc.org/code

for AISC 303-05 Standard Code of Practice.......lists fabrication tolerances, starts on page 27

 

[abusementpark]

So, have you guys ever dealt with fabrication errors explicitly in your structural analysis??

 

[jike]

Everyone makes mistakes including engineers, GC's and fabricators!

Misaligned holes, painted or unpainted beams, turned base plates, connection on wrong face of column, building out of tolerance, etc. (which made it to the field). Fortunately, these mistakes are generally few and far between and were not too serious, which goes to indicate how great our fabricators really are!

The only serious ones that I remember were wrong beam size, missed welds, undersized welds, no camber, etc. (which were all caught on shop drawings).

You will only know if you or your representative are making regular inspections.

 

[Ron]

jike pointed out the key...inspection.

Shop fabrication inspection, field inspection, special inspection...all have a place in construction.

At one time had the task of being responsible for the off-site inspection of structural steel for "a major theme park in Central Florida". We had a full-time inspector in each fab shop, with NDT inspectors floating between the shops. You might think that having an inspector would make the shop work a bit harder at quality...well, it did, but the inspectors still earned their pay by finding non-compliance issues every day...Undersized welds, non-conforming welds, layout/fitup problems, wrong sections, etc.

Then when it gets to the field, you'd think the steel erectors were electricians....as long as it touches it's OK.

Over the years have seen many more field problems than shop problems. Most shop problems were associated with complete penetration welds.

As for analysis...unless it's a gross error, the engineer doesn't always get to offer any input, unless there is a mandatory inspection process (special inspection,etc.) that requires documentation of the fix.