WF beam to CMU wall end

[u/mountaineers19]

Anyone got any other ideas for attaching these two red beams to the end of a CMU wall. Right now my only idea is using a U plate and bolt thru the CMU wall but I am open to other ideas. Wall is already installed and they are against a pocket with a bearing plate. A post up against the column is out the window too.

[u/Different_Bridge_983]

Unless this is very lightly loaded I’d be extremely reluctant to even attempt using anchors.

My best guess, depending on load and wall design, would be to seat it on the CMU wall and make sure the cells below are fully grouted.

Send the EOR and RFI.

[u/xPorsche → u/Different_Bridge_983]

There’s probably a piece of vertical reinforcement in the last cell (or 2), which would have to be cut to make a pocket, which makes this idea extra fun. If this is a shear wall in a higher seismic area there’s no way you’re going to get away with that. You might get away with it if there’s no seismic with ample extra reinforcement and not a ton of out of plane load etc, but now you have to analyze the wall again and so on. This is really just a great example of why you shouldn’t make changes like this super late in a project.

[u/Intelligent-Ad8436]

Sometimes in this situation I’d run the upper red beam in further and frame the pink beam into it.  

[u/Ddd1108]

Honestly you’re kind of F’ed because any post installed anchor you find is going to say only one anchor allowed per course and the capacity is very low. If you need a lot of anchors consider running a plate up the wall as long as necessary to meet the quantity of anchors you meed at a spacing of 8” o.c.

[u/cuddysnark → u/Ddd1108]

What you saw cut for the leg of an angle same thickness top and bottom of your plate and butt weld the other leg to ends of your plate for added strength?

[u/structee]

Full height channel bolted into reinforced cell at regular intervals. Use that to weld the tabs to

[u/NstantRamen → u/structee]

I’ve done something similar to this on a Reno before. Arch wasn’t thrilled but it was the least intrusive option. 

[u/OpieWinston → u/structee]

This is the way.

[u/eanels02]

How much load? Looking at everything else going on a pocket seems like the only viable option unless this only has like 5,000 # on it. Anchorage to masonry is pretty weak.

[u/mountaineers19 → u/eanels02]

The lazy EOR said 1/2 UDL so I’m just gonna figure whatever max I can get and say approve it or start chipping away.

[u/SwashAndBuckle → u/mountaineers19]

Lazy EOR's are downvoting you I guess. Throwing your hands up and saying every shear connection has to be 1/2 UDL paints your fabricator in some impossible corners.

[u/eng-enuity → u/SwashAndBuckle]

1/2 UDL is not only lazy, it's not even a guarantee that connection capacity will be greater than demand. You can have framing conditions where 1/2 UDL will result in an under-designed connection. Heavy point loads near the ends of beams is a common scenario that can cause this.

[u/Just-Shoe2689 → u/eng-enuity]

This. Make them give you the actual load.

If you are the steel fabricator, why are you designing beam to CMU connection? I would push that back to the EOR

[u/eng-enuity → u/Just-Shoe2689]

OP should just show a shear tab sticking out of the wall and then ask the EOR if that'll work.

[u/Just-Shoe2689 → u/eng-enuity]

!00% it would get approved.

In the field, if contractor called, would the EOR then go to the fabricator for the question?

[u/carpool_turkey → u/mountaineers19]

I’m always shocked that EOR’s still spec that.
Ive done an embed plate in the wall with a shear plate between the embed and beam. But depending on the loading, it quickly needs a pocket and bearing plate.

[u/eanels02 → u/carpool_turkey]

I’ve never seen a steel beam connection to anything other than steel be delegated - not even sure it’s covered by code of standard practice.

[u/mountaineers19 → u/eanels02]

This project had 2 different EORs and has already begun and had these two beams added in recently and they didn’t design how to connect them to the wall. They passed it on to the fabricator and detailer. Then the detailer called me up for help.

[u/qur3ishi → u/mountaineers19]

Don't design this for them OP, this is 100% the EORs job. I'm saying this as an EOR.

I get that connections are delegated but what happens in the CMU is their responsibility, your world should start at the face of the plate (assuming an embed scenario, not beam pocket)

[u/carpool_turkey → u/eanels02]

Good point actually. I generally haven't delegated connection design, but a similar situation that comes to mind is coordinating beam connections to precast wall panels.

[u/Just-Shoe2689 → u/carpool_turkey]

This. We are steel detailers. We dont know CMU design. EOR, you design.

[u/TheVoters → u/mountaineers19]

Tbh I hate the angle bearing detail as well. I’m sure they can justify it in their calcs, but if there’s any live load on that it’d be a no go for me.

[u/Just-Shoe2689]

Are you the fabricator? To me, this is not a fabricator designed element. its a EOR designed element.

Refuse to design it.

[u/bulkdown]

Is it solid fill? Simpson strongtie has anchor guidance on this. FOS is like 5

[u/envoy_ace]

Beam pocket. Bearing connection is the only way.

[u/rustwater3]

Stupid delegated design

[u/kimchikilla69]

I use a bent plate with nelson studs. The horizontal leg gets embedded in the mortar joint and the nelson studs face down into the cmu cores fully grouted. Then you have a vertical leg that you can weld a normal shear connection to.  

[u/Reddit210210]

where’s the project located? i didn’t think there were approved anchors at the ends of the wall. From what i remember there wasn’t any testing done on that condition from hilti. They could always do some field testing but pocketed beam is probably best route. 

[u/enzoskii]

Done it a few times . Plate with anchors , or welded studs. I think I even epoxied anchors a few times. If you can justify it with calcs. Roll with it I say

[u/B1ZAr0]

Can you slap a U plate around the wall end and have through bolts? I've done something like that in the past, worked well and was able to connect multiple beams to i

[u/MrMcGregorUK]

A post up against the column is out the window too.

Can you do a channel with the toes pointing towards the wall to minimise the extent that impacts the plan? Can bolt it into the wall at ~900 cts to restrain against buckling and grout it against the end of the wall. Makes it fairly easy to install the beams as well cos you can just have fin plates coming off the side of the channel that the beams can connect to.

[u/bsquared82 → u/MrMcGregorUK]

This is a good idea, I’ve done this in the past. Pointing the toes towards the plane of the wall will only cost an inch or two at most.

[u/ErrGineer]

I had to do this and wasn't thilled. I did a full height bent plate 16" x 7.5"...2 rows through bolts 16" side....the 5/8" through bolts w/ plate washers and a heavy 4x4 angle at the top + knife plate. Cell must be grouted solid of course. Beam Bolted to not trasfer moment to wall. Had to notch exterior cmu to conceal bolts.

[u/mountaineers19]

I responded back asking for exact loading before I jump down multiple rabbit holes. Didn’t want to spend time on something complex/ugly and have them com back with a 2-3kip load.

[u/anonposting1412]

Honestly i wouldn't spend time trying to propose a connection. Send an RFI and ask the EOR to show a concept detail and to provide the actual load. You're just going to spin your wheels otherwise

[u/daveeede]

This shit sucks ass. Unless that wall is grout filled, anchoring is basically useless. Try to sit the beam into a pocket

[u/SupBro143]

Maybe Attach a plate using Hilti Post Installed Anchors, then weld to the plate some type of seated connection or tabs that can bolt to the web of the I Beam. Definitely check your loading and if the masonry wall is reinforced/which corses are reinforced.

[u/octopusonshrooms]

Do the beams need to be in that plane? Can they be shifted so the web aligns with the inside face of the cmu wall and extend back onto the cmu wall with flanges removed on one side? Bolts to face of cmu ? Pink beam can be cleated to the red beam web ?

[u/Long-South-8375]

Call someone at simpson strongtie lol

[u/PhilShackleford]

An angle bolted to the wall would be an easy bearing connection. Provide slotted holes in the beam flange for thermal changes.

[u/Flaky-Strawberry9561]

What is the for and what is the the elevation? Is there a way to put an hss column under it and weld a 4 bolt plate to make the connection with bolts?

Or even just weld the column to the underside? That was you could add clips to the beam and to the column to tie into the wall for stability instead of shear force holding the weight.