Design Documents 2

[SteelPE]

What does is mean when an engineer requests information in a design document format? I though design documents were the plans and details prepared by an engineer.

In this instance we are required to send sealed connections to the EOR through the fabricator. The drawings required information submitted to the engineer in a "design document format not a shop drawing format". I sketched up the connections and sent them over. Now they are requesting calculations to back up my design. Not that big of a deal just a little PITA.

 

[ukengineer58]

we submit calc docs for almost all our jobs. some have third party checks by another firm or building control. this is uk

 

[ztengguy]

I think they mean drawings and calcs from you, not second hand shop drawings or fabrication drawings with your stamp.

 

[SteelPE]

I was just surprised about the calculation requirements. The connections were simple shear connections. I don't know what I am going to give them for calcs.... other than photocopies of the ASIC 13th edition steel manual.

 

[dhengr]

It seems to me that the whole business of Structural Engineering and design has become a PITA. I assume you are doing the connection and detail design for the fabricator, in part because the EOR was too dumb or lazy to do sufficient design and detailing so that the connections could be shop detailed. I suppose his computer software couldn’t do this, for him, during his nap periods, so he put a note on his drawings saying he wanted someone else to blame for the connections. Let’s have twelve different engineers stamp this two-bit job, so we’ve got plenty of people to blame if something goes wrong, lots of deep pockets, all being underpaid for their effort and knowledge, or lack thereof. Pretty soon we will need a different engineer to stamp welded connections vs. the bolted connections. And, the bolted connections are a real PITA because you need a different engineer’s stamp for each different bolt size, and others for bearing or slit critical connections.

Since you are working as an extension of the fabricator, as his engineer; I assume you have talked the details over which need your attention, and so they can start detailing the job. You have to do enough free body diagrams of the connection to do your own design, or you might take a 8.5x11 copy of one of the shop drawing details, in its initial form, without final spacing and dimensions, etc. and red-line it as part of your calcs. You need to show sufficient detail to do a complete, clear and proper design, but I would not worry that my calcs. and sketches look like Rembrandts unless they want to pay you for this. You must show enough to do it right and to be able to defend your design, but you do not have an obligation to educate the EOR. He wasn’t smart enough to do it himself, or was trying to push the work off on someone else to improve his profit margin; it’s your stamp and responsibility on that portion of the work, and a fair and reasonable discussion of questionable conditions is understandable, but you shouldn’t have to redo your calcs. because you left out the calc. step of converting ft.-kips to inch-pounds. If the AISC connection tables are sufficient for your design of simple shear connections, I would state that in a note in my calcs. and that they were done to the loads shown on his construction documents and let it go at that.

These types of issues in the whole design, detail, build sequence of events are starting to boarder on insanity. Everyone, at every step along the process, is looking for someone else to do the work, take the blame, have the deep pockets; all because they aren’t smart enough or are too lazy to do a complete job themselves.

 

[SteelPE]

dhenger

Must have hit a nerve there sorry.

You would be shocked to see what this "job" entails and what the EOR is asking for. There are literally a hand full simple shear connections (9-10 in total) all worked out to 3 different cases. Two tab plates and a double angle connection. I drew them up, sealed them and sent them out for approval. I gave sufficient information to build the connection (angle size, plate size, bolt size, weld size and dimensions). Well they came back requesting calculations backing up the design of the connections. I literally opened up the 13th edition to create my sketches using tables 10-1, 10-2 and 10-9. Their general notes require sealed connections that are "in a design drawing format not a shop drawing format". I just never knew a design drawing format included calculations.

Now they are requesting I design hand rail attachments down to the blocking the hand rail is attached to.

I get paid to perform the design either way..... I just feel a little sorry for my client.

 

[JedClampett]

dhengr, you might be surprised on how long it's been this way. Connection design, in particular, has been deferred to the fabricator for many years. I don't like it either, but when I started, one of my first lessons was that we assumed that the connections were to have the capacity of an AISC Type II connection unless we posted a higher load (or made it fixed), but in all cases, it was the fabricator's responsibility. When I asked why, I was told it was too much work to design all those connections.
As fees are driven ever downward by lowball competition, engineers have become quite clever at doing less and less design. And the funny thing is that the work has to be done, it's just changed who's doing it.
I don't have a solution. I'm just along for the ride.

 

[ukengineer58]

in uk connections are almost always done by fabricator to loads on structural plans. we then review them.

 

[dhengr]

Not much shocks me any longer, it’s just the sheer (not shear) stupidity which puzzles and amazes me. The utter inefficiency, laziness, expense, consumption of extra time and effort, etc. etc. of having to involve five people to do the work of one. All to hide the laziness or lack of knowledge and experience on the part of the primary designer. All of this at the owner’s expense, and we lie to him in telling him he is getting a better finished building, in doing it this way. When I’m designing that beam, I know the shears, and it only takes me a few seconds longer than printing the shear values on the drawing, for me to pick an angle and a weld size, tabulate these on the drawing and be done with it. Hell, copy and paste the AISC table into the drawing and number each line A1, A2, etc. and show those Ai’s on the beam ends and be done with it. Each time I require you to get involved for a few simple shear connections, through the fabricator and back and forth to me, it’s a few thousand dollars out of the project budget, for no real gain to the client. It’s absurd. And, then I can really antagonize you by insisting on your calcs. and CAD drawings, not sketches, to my format, and then red-lining the hell out of them over insignificant issues. You are no longer my helper or cross checker of my work, I have made you my nemesis.

I do understand the need for some special help on a complex enough structure or complex enough detailing and connections, that may be money well spent, and advice well worth it on some jobs. But, the real proof of that pudding is that if the EOR isn’t smart enough to do those complex connections and details, he probably shouldn’t be pretending to be the EOR on that kind of job. If he’s not smart enough to do the whole design, how is he ever going to be smart enough to check your work. Or, is the whole idea, now that I’ve got your calcs. in my file, I’ve got something to hang you with; even if that future project problem was of my own making, I’ll force you to help cover my mistake.

Consider this also, maybe you have misread the structural notes and specs. Maybe “sealed connections” means a seal weld all around, and you’re wasting your time with all those calcs.

 

[msquared48]

Design of steel connections by the fabricator is an east coast thing, not west coast, I always design these, no matter what.

However, the fabroicator does detail them for the shop, and I check them.

Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[SteelPE]

dhengr

I don't think I misread the documents. The general notes required designs carried out by other professionals to seal and sign their work. Then we got a letter explaining to us their definition of design documents includes calculations

 

[connectegr]

This practice is near and dear. Our firm has provided only connection design for nearly 21 years. In addition to the connection sketches we always provide the support calculations. Although the simple shear connections are shown in the manual, all of the limit states are not checked for the provided capacities. For example the clip angle or single plate tables don't check the beam web bearing, block shear, cope capacities, etc. Our standard tables make these considerations, but back-up calculations explain the capacities given to the detailer. These are not difficult to reproduce. A set of standards and backup calcs take minutes, not hours to complete. The majority of the time is spent determining the fabricator preferences, bolt diameter, welded/bolted, angle thickness, plate thickness, etc. The rest is just a few clicks.

http://www.FerrellEngineering.com

 

[jdgengineer]

In California, The EOR has been responsible for the connection design for every project I've been on.

 

[archeng59]

I design and detail all of my connections. If I have to review them anyway, might as well take the time to design them as I prepare the drawings.

 

[ukengineer58]

but what about fabricator preference? they now what they have got access to and what they are set up to do. a designer might not even know the fabricator that will be used.

 

[archeng59]

I have been doing this for almost 20 years. I know the fabricators that I typically work with in my area and my details are based on the typical connections they like to fabricate. If they want to do something different, I either ask for an RFI or tell them to put it on the shop drawings and I will review.

 

[hokie66]

When did this change in the eastern part of the US? I worked in Virginia until 1982, and connection design was part of the structural design engineer's work.

 

[connectegr]

This has been the trend west of the Rockies since the mid 80's. In large part due to the Hyatt collapse. I can argue for hours the advantages of delegating the connection design. In addition to designing connections for the fabricator we design connections for many of the premier design firms. This can be a very specialized design practice, with cost impact on fabrication, detailing, and erection. Which have a much larger project cost than the structural design. Some of our projects require many more man-hours for connection design than the structural analysis. Most engineers understand the design principals of the connections, but very few have the time or opportunity to learn the fabrication and erection considerations.

I believe the engineer of record should insist on direct communication with the connection engineer. Working together I have found a project benefits 100% of the time.

http://www.FerrellEngineering.com

 

[connectegr]

The delegation of connection design is also recognized for the first time in the 2010 Code of Standard Practice.

http://www.FerrellEngineering.com

 

[hokie66]

I am sure you do a great job of connection design, connectegr, but I will never agree with the philosophy of splitting that responsibility. My question was about the East, but you indicated that delegation is trending that way in the West as well. Others here, in California and Washington, seem to say otherwise.