How much capacity would you allow in this connection? 2

[XR250]

See attached. (2) 1 3/4x18 LVL notched 8 3/4" to sit on double top plate. Simpson HU410 hanger with some nails in double plate and some in LVL header. Looks like the hanger would have a capacity of 2,300 lbs if fully nailed in a solid member.

 

[KootK]

I vote 2,300 lbs prorated to discount any nails in the top plates that would have questionable edge conditions in those top plates. I think that you'd have to assume that the notch would fail before fully sharing its load with the hanger. Ergo no concurrent capacity. If need be, you could drive some long GRK screws up through the depth of the thing to reinforce the notch.

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.

 

[XR250]

Ugh, I was figuring that myself. The contractor is OK with me designing some sort of unsightly ledger system that would not be hidden by the sheetrock (it is a garage)
I can't imagine the owner liking that. I wish these guys would call me before they get in trouble.
Might also could cut back some of the joists and sister some un-notched 9 1/4" LVL's to the side of the 18" LVL.
I need about 5,000 lbs total.

Thanks!

 

[JStructsteel]

what about a steel angle thru bolted to make up the difference, or up the sides with angles?

 

[jayrod12]

I guess the question would be, what has more shear capacity, the remaining portion of the LVL that is sitting on the top of the wall, or the hanger?

If my information is correct, the LVL should have significantly more capacity even in it's notched state, then the hanger. Depending on how tight it is cut, and the bearing on the top of the wall, I might be persuaded to use whichever capacity is higher. Not additive, but either or.

 

[XR250]

I guess the question would be, what has more shear capacity, the remaining portion of the LVL that is sitting on the top of the wall, or the hanger?

If the LVL was 9 1/4" and un-notched, it would likely be fine. Does the notch have the same effect as it does on dimensional lumber. I have always heard it does, but intuitively, it seems that the ply'ed nature of the LVL would not be affected.

 

[XR250]

what about a steel angle thru bolted to make up the difference, or up the sides with angles?

Am drawing that up as we speak.

Thanks

 

[nac521]

Replace with an HGUS48 hanger

 

[Shu Jiang PEng SE]

for bending member with notch on the tension side, the design shear is V=2/3*F*b*dn(dn/d)^2. The design shear due to lvl should be very small and ignored. The shear provided by the hanger is determined by the number of the nails nailed to the double plates.

In one word, it does seem not be a reasonable connection.

 

[XR250]

Replace with an HGUS48 hanger

I am worried that the header will get too beat up if they take off the old one.

 

[jdgengineer]

I would use the capacity of the hanger as mentioned by KootK. I would not consider the notch without running the notch past the LVL manufacturer and having them provide acceptance in writing. It exceeds the allowable notches of 8.4.1 of the NDS and likely their ICC report.

 

[KootK]

Without digging to deep, the stock T-side notch limit seems to be 0.1D: Link

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.

 

[jayrod12]

I'd still be making an argument that a single ply 5 1/2" deep LVL member is good for almost 5000lbs shear. you have almost double that depth left, you should be able to get some capacity out of it that's higher than the hanger load. Are you going to get anywhere near the capacity of a 9 1/4" deep, nope, but surely you could get at least 5 1/2" deep. However, in the end, this is a question for BC or Weyerhause directly likely. The technical paper Koot posted surely gives some direction, but I'd want to hear it straight from the horse's mouth.

 

[molibden]

Glue plywood boards on both sides of the LVL to reinforce against splitting. If the remaining height of LVL can take the shear then I would definately do this. Seems like a better idea than using screws because LVL elements are relatively thin and have vertical orientation of plies.

 

[HouseBoy]

Although it SEEMS like a 9" LVL would be fine, I say that Xain is right. Allowable shear is reduced by the square of the remaining percentage of section (in addition to the reduced section available to resist shear). Used to be NDS only reduced by the percentage of remaining section but they squared that awhile ago (maybe 2005?). Anyway, they must have had a good reason for that.

Unless you can reinforce the notched LVL so that you provide the horizontal shear capacity of the full section, I think the notch makes it worthless in shear.

Interesting 2x4 ledger they've got there on the side of the LVL beam for the 2x10 joists framing into it.
That's "old school" (i.e. I don't see to much of that detail anymore). Looks like that ledger is going to make it tough to install shear reinforcement that molibden is suggesting.

Is external shear reinforcing like a CF strap possible?

 

[KootK]

Seems like a better idea than using screws because LVL elements are relatively thin and have vertical orientation of plies

I agree. I didn't think that through. XR does't pay me enough for a detailed construct ability analysis.

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.

 

[XR250]

Ended up designing a bolted steel hanger at the direction of the contractor. KootK has been fired.
Thanks for everyone's thoughts.

 

[bhiggins]

Care to share your final design? I'm curious what a custom steel hanger would look like. Saddle with flange plates welded to the side? Would a bolted double angle connection be OK for this situation?

 

[XR250]

here is a prelim design...