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concrete joint reinforcing details 2

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cjung

Structural
Dec 1, 2016
19
I am currently involved in a Transit Rail Station construction project. This is a Design-Bid-Build project. We are having many reinforcement detail issues with the designer, especially, regarding missing highly congested concrete joint reinforcing details. The design drawings do provide individual reinforcement details for each beam, column, slab, pier cap and etc. However, there aren’t any combined joint reinforcing details. I used ACI 315 to claim that the joint details needed to be provided by the designer. (I am referring to the special moment frame as well as ordinary moment frame reinforcement details) However, the designer answer is per ACI 315, the contractor needs to provide the joint details then the designer approves the shop drawings.

I am looking for a specifically which code or any specification should I refer to the designer that the combined joint reinforcing details are required to generate the shop drawings.

I appreciate your help on this matter.
 
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JAE:
I got ACI 132R-14, and found useful information. Thank you so much for the information.
The design engineer is claiming that ACI 132R-14 is not the part of ACI 318 and 315 (these two codes were only mentioned in the general notes). So, we cannot refer to ACI 132R-14. How can we relate ACI 132R-14 to our design drawing reinforcement joint detail issues? All we want is that the designer must provide the missing joint reinforcement details in order us to generate reinforcement placement drawings?
This is the design-bid-build project. ACI 132R, SECTION 6.1. states "General contractors have a right to assume that contract documents reflect all applicable code and other owner-imposed requirements". Does this statement only exist in ACI 132? I am looking for similar statement in ACI 318 or ACI 315.



 
Sounds like a lousy SEOR. I don't know if this will help, but ACI 318-14 has the following in the commentary for Chapter 26 Section 1 - Construction Documents and Inspection:
"The construction documents should contain all of the necessary design and construction requirements for the contractor to achieve compliance with the Code. It is not intended that the Contractor will need to read and interpret the Code."
It goes on to state,"A general reference in the construction documents requiring compliance with this Code is to be avoided because the contractor is rarely in a position to accept responsibility for design details or construction requirements that depend on detailed knowledge of the design." It seems like this may work, but I'd be prepared for push back trying to use this because I don't believe Chapter 26 explicitly lists detailing joints as a requirement of the design professional.

Note that 26.6 deals with "Reinforcement materials and construction requirements" and notes as a requirement under Design Information that the design professional must show the type, size, location requirements, detailing, and embedment length of reinforcement.
 
It appears that the EOR is trying to delegate design to the contractor. For the EOR to do this, they need to identify on their plans that certain aspects of the design are delegated.

I don't know what building code you are under but in the IBC, section 107.3.4.2 talks about this. Technically the building official has to approve of any deferred submittals. This is usually done via the EOR showing on the plans that certain items are "by others" or specifically listing the deferred items and the building official, upon reviewing the plans, approves them for construction.



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Thanks JAE and Mike20793:

I would like to share my RFI(BLUE) and EOR's response(RED). Please help me. All i want is the reinforcement details provided by the EOR, then we will generate SHOP drawings. We're stuck with EOR.
Do you know where it says, the lap splice details and locations must be provided by the EOR?

According to ACI 315, Section 2.8 – Joint Details, “The A/E must provide complete information, showing the radius of any nonstandard bends and location and dimensions of lap splices. If a mechanical or welded splice is to be used, a physical description must be provided.”
(This is true. If nonstandard hooks are needed, they are required to be shown. If not, then you should only need to state “standard hook”. Looking through the structural drawing (example ST330.1 below). Both standard hooks and nonstandard hooks are clearly identify. If hooks are just shown without specific bends indicated. They should be assumed standards.) If there are locations with nonstandard hooks and they are NOT called out, they should indicate which detail and the EOR will provide the response accordingly.

1. Provide reinforcing details for all joints in the reinforced concrete structures referenced above.
Details for the joints connection shall be in accordance with ACI 315 as required in General Structural Notes and Project Specification Section 03 20 00, 1.03
It is the responsibility of the detail to detail the reinforcing in accordance with ACI 315 – NOT asking the design team to provide those details.


2. Specify the lap splice locations for all reinforcement.

THIS IS A REQUEST THAT NO CONTRACTOR SHOULD ASK. THE EOR CAN JUST SAY NO SPLICE REQUIRED. THE SPLICE LOCATIONS ARE FOR THE BENEFIT OF THE CONTRACTORS WHO CAN’T GET LONG ENOUGH REBARS OR WOULD LIKE TO SPLICE THEM FOR EASE OF INSTALLATION.
 
This job site is located within the states.
AISC has the solution center to ask structural steel related questions.
Do ACI have similar?

Does anyone know how to contact ACI for the code interpretation questions?


 
Wow, that sounds incredibly confrontational. I'd start looking into mediation by a neutral party or whatever equivalent option is in your project specifications/contract.

If possible, can you post redacted copies of the detail and specification section referenced by the EOR in your RFI? It might help us to know what you are at least given to work with.

I don't know of a similar ACI solutions center, I'd try their website email support and see if they can point you in the right direction. If you're an ICC member perhaps you could also request an interpretation with the ICC. I'd also submit to the EOR IBC section 107.3.4.2 as pointed out by JAE above. Unless this was spelled out clearly that these details were "by others" or required submission to the EOR I would fight this tooth and nail.

Professional Engineer (ME, NH, MA) Structural Engineer (IL)
American Concrete Industries
 
Both your RFI and the response are not helping the situation. We don't know what the drawings look like but you state that you have information for the individual members, it appears that you are requesting that the EOR provide you with details of the joints. If you have the details of a column and beam you have the configuration of the joint.

1.) If you have a question about a specific issue you should ask that. You are using the reference to 315 incorrectly, it does not mean the EOR is to provide you with shop drawings for you to reproduce but to provide the information needed to make the shop drawings.

2.) Don't know what the drawings look like so cant gauge who is correct.

3.) Engineer is completely wrong, ACI 318-11 1.2 (i) specifcies for the contract documents to specify the location and length of lap splices. It could be that the splice locations are not critical on the project. As an example our drawings typical call for splices to be staggered between layers of bars but we dont provide locations as it is not important on general footings etc. We will show locations when it is critical, special moment frame beams, shear walls, grade beams etc. If no limits are given then you can place laps as required. I have had contractors request splice details for and always set limits on locations.
 
I made some sketches to make my point clear.
Attached file: Page one depicts concrete layouts of a portion of the structure, second page depicts individual reinforcement details from the contract drawings, and third page depicts another joint case.
I asked EOR how to combined individual reinforcement details at each joint area. The first page structure is the intermediate moment frame, SDC C, and the third page structure is the special moment frame, SDC D.
My statement is that we as a contractor cannot produce the combined joint reinforcing shop drawing based on the individual reinforcement details in the contract drawings. We believe the joints are heavily congested, and we do not know how to place the reinforcement per the Code requirements, because we cannot find the joint details in the contract drawings.
 
 http://files.engineering.com/getfile.aspx?folder=3da55214-af82-4ee2-ac80-8e3c0281a8f0&file=DOC004.pdf
Notes or details should indicate what to do if bars terminate in the column or if the bars continue thru. These could occur in typical hook details or notes, I have always seen them in elevation of the typical beam bays. If these are all the details provided I would say that you have need for splice locations of the columns at moment frames, along with splice requirements. You are not going to get a detail showing the location of each individual bar and interaction of other bars and the EOR would not need to provide.
 
As far as I've seen, all of the "responsibility" documents say more or less the same thing:

1) EOR must give detailer all of the information that they need to sort out the detailing without making reference other documents such as the code. This can, and usually is, done by way of details that are general in nature rather than specific. They'll show you a detail to apply to all joints of a sort rather than a detail for each particular joint.

2) Detailer must use EOR drawings to prepare bar placement drawings which are then reviewed by the EOR to see that they satisfy the EOR's intent.

So it's a two step process. EOR gives you stuff to work with; you give them something to review.

Based on what you've shown us so far, it seems that the EOR has done an insufficient job of step #1. Shame on them. Moreover, most EOR's would be grateful -- although perhaps not happy -- to have the detailer report congestion problems before everything gets out to the field. Again, shame on your EOR for, apparently, failing to appreciate your help in that regard.

So what to do? I see two avenues of resolution:

1) Keep asking for the additional details until you get them.

2) Do your best to detail things yourself per the code. This has some advantages and disadvantages:

DISADVANTAGE: You have to sink more time into the work and run the risk that the EOR will reject it and make you do it over again. Truly, it's not fair to you. That said, you're obviously spending a fair bit of time and energy trying to coerce the EOR into being helpful. Which route is the most costly for your firm is your call.

ADVANTAGE: When all is said and done, the detailing will be the EOR's responsibility, including any congestion problems. So at least you don't have to worry about that.

If it were me, at this point, I'd probably do this:

1) Send the EOR something in writing saying that you've identified congestion issue and you fear that the joints will not be constructable on site and/or will result in lousy concrete consolidation. Copy your client who is, presumably the general contractor.

2) Send the EOR something in writing saying that, since you're flying blind with the connection details, your firm will be seeking remuneration for any associated rework that is necessary. Copy your client.

3) Take a stab at detailing the connections without the extra information from the EOR.

If your EOR has any business acumen at all, or reports to someone who does, they'll start cooperating before you get to step three. It sounds as though you've already made a hearty attempt at banging the cooperation/responsibility drum. Some folks only respond when you switch gears and start speaking the language of consequences.



I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
 
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