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Shop Drawings, No Calculation Package 14

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EngStuff

Structural
Jul 1, 2019
81
The company I work at we designed a steel building, and we are the EOR. We got the shop drawings for the steel building, but no calculation package. In our general notes we have the language of the details being standard details, and they need to have an engineer to design the connections. We also state to send over stamped calcs for us to do a quick verification. Contractors and clients want to move the project forward without worrying about us checking the calcs/connections. Just make sure the steel beams/columns and E sheets are representative of the structural drawings.
One of the engineers here is saying we perhaps can add a big Note stating that we did not check the calculations nor the connections they provided, and we only checked the configuration of the steel members and exact sizes and are not responsible for connections and they must provide calculation package for record.

In addition, we would stamp it as “approved as noted.”

When it comes to liability, how liable are we if the connections are not sufficient and a failure occurs since we are the EOR? Is there any other recommended language or additional note to add?
 
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Can you review the structural beam sizes if you don't know if the connections are moment resisting? Is that something left up to the fabricator or noted on your drawings?
 
“It has been done that way forever” is no excuse. And by the way, that statement is incorrect. Delegated design of connections is a relatively new (and flawed) concept.
 
hokie66 said:
“It has been done that way forever” is no excuse. And by the way, that statement is incorrect. Delegated design of connections is a relatively new (and flawed) concept.

I'm interested in your perspective on why delegated design of connections is flawed.

As for the history, I can just say it's been that way during my career, but that's less than 30 years. My understanding is detailers used to "design" the connections before that, so the situation might've been worse. When was the phase when it was typical for EORs east of the Rockies to design the connections?
 
If EOR is still responsible for delegated design, what does this mean for general/municipal civils that rely on engineered designs for, say, a precast box culverts, manholes, and junction boxes that get installed on many municipal projects? Is the only correct way to subcontract a structural engineer to design these and cast in place?
 
I'm not sure the connection that failed in hyatt regency was delegated, as far as I understand it is shown on the engineering drawings. Rather, the fabricator changed it to be more erectable. If anything, more delegated design would have helped - had the fabricator had a connection engineer who understood the forces, it could have been arranged more rationally.
 
I killed some time at work reading into the case because I was interested.. It was deemed a "special connection" and there were no connection details or intended loads on the structural drawings. The EOR said in the hearings that it was intended for the fabricator to complete the design of the connections. The shop drawings did propose a different connection than what was initially proposed, but the EOR said that the connection in the shop drawings would be fine (without doing any checks).
 
The point about the Hyatt isn't that delegated vs eor designed connections are better or worse. Its that the EOR has the ultimate responsibility for the construction. Regardless of delegated designs, regardless of fabricator error. The EOR is where the buck stops. At the Hyatt there were at least 2 issues leading to failure. 1 The connection was under-designed to begin with by the EOR, 2 The connection was further compromised by a change by the fabricator on the shop drawings, and the EOR approved it!

The EOR is responsible to verify that delegated designs meet the design intent of the construction drawings. We don't just call out delegated designs, then turn the blind eye to them and say 'Well its not my stamp'.

For general/municipal civil I'm not so sure how it works, but there should be a contract document that establishes the required design criteria stamped by the EOR. The eor is responsible to ensure that the deferred engineering work meets or exceeds those requirements and that the design is safe.



 
271828,
I can only speak to the situation in Virginia before 1983, and we structural engineers designed our own connections, then checked the shop drawings to ensure they followed the design intent.
 
For the last three years I've been designing connections for steel fabricators... there is no problem with this. When I did design work on projects we would stipulate the design loading for the metal fabricator's engineer to design and seal. This was taken at face value and was delegated... as the designer, I never required proof that the bolts were really A325s, either... or that the material was as spec'd... this too was delegated... There is nothing wrong with delegated connections; it allows someone that specialises in this work to undertake it in the most economical fashion possible.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
driftLimiter said:
...Its that the EOR has the ultimate responsibility for the construction. Regardless of delegated designs, regardless of fabricator error. The EOR is where the buck stops.

Yes

 
What's the reason the fabricator isn't responsible for fabrication errors?
 
The fabricator is responsible for his own errors. But in cases of major failures, everyone involved in the project can be at peril of litigation, especially those with deep pockets.
 
@stevenh49 I suppose I should qualify my statement a bit better. The EOR is responsible to provide a safe design. Fabrication error after approved shop drawings falls outside of design and now into construction defect, EOR not responsible for that. Hopefully a good QA/QC is in place to catch it.
 
The EOR may delegate tasks, that includes responsibility for the extent of his checking of the delegated design. He can not delegate the responsibility for a safe design product, to the design is no longer under his responsible charge.

As discussed above we have evidence that taking shortcuts with responsibility has consequences.

[URL unfurl="true" said:
https://en.wikipedia.org/wiki/Hyatt_Regency_walkway_collapse[/URL]]
Screenshot_from_2023-01-26_18-01-35_vq520l.png

Edward Pfrang, lead investigator for the National Bureau of Standards, characterized the neglectful corporate culture surrounding the entire Hyatt construction project as "everyone wanting to walk away from responsibility".
 
It's best to explicitly call for Option 1, 2, or 3 as called for in the AISC Code of Standard Practice. This is the closest thing to being "covered" in terms of liability. It also outlines the various parties' responsibilities.

That said, the provisions still induce several pages of commentary, which tells us that connection design is a bit of a sticky wicket, regardless of the option chosen.
 
Hi all!

A Quick update, essentially what my boss told us to do was to check them, note whatever is obvious in addition to the calcs required. stamp it as reject and resubmit. To paraphrase what he said. Someone messed up and it's either the contractor or fabricator. They had all this time to supply required signed and sealed calculations by an Engineer. They also know they have to provide them majority of the time unless it's a complicated connection. They know they have to hire an engineer to design the calculations. We did our due diligence and provided what we are supposed to as EOR. If they missed the deadline, it's not our problem. They can make up for it another way and not have us be the scapegoat.

I noticed a question about delegated design. I remember one of the engineers here stated that most the times if we provide designed connections. We tend to get bothered to change them to either bolts and/or welds. So, it's easier to provide standard details and give them freewill to detail it how they please (within standard limits) and as long as they have an engineer provide a signed and sealed calculation package for us to review. There are some complex connections that we still provide a design for because of different loadings.
 
Where I worked from my graduation from university about 1965, up to about 2017 (I partially retired about 2006; fully retired about 2017), our shop review drawing stamp was changed to remove the word "approved".
This was after we asked a law firm to review our procedures, documents, etc., and they advised us to replace the word "approved" with the word "reviewed" and never to use the word "approved" in any document or correspondence.

The note on the shop drawing review stamp said that some, but not all items had been reviewed for "general conformity" with the design drawings and specifications, etc. ... I cannot remember what the exact wording was, on what then was a "rubber stamp". That was a different era; I imagine that today drawings are CAD and shop drarwing review "stamps" as well as mark-ups, are in CAD.

The lawyer who advisedd us, had graduated as an engineer, and then later graduated in, and practiced law. So he had a good understanding of engineering, and never asked us to do things that were not in accordance with good practice and ethics. He was a unique person. Unfortunately he passed away reltively young.
 
ajk1 - despite your attorney's suggestion, I've had other attorneys say that changing the wording on a review stamp doesn't really accomplish anything.

In fact, and unfortunately for the assumption that "approved" is bad, AISC specifically requires EOR's (Owner's designated representative for design) to "approve" submittal documents.
See section 4.4 of the Code of Standard Practice where it states: [blue] "Approved approval documents shall be indiidually annotated by the owner's designated representative for design and construction as either approved or approved subject to corrections noted."[/blue]

 
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