Brick Shelf Ledger Angle Design 1

[MaxMedic]

Hello, I am looking into checking to see if what is shown in the section is sufficient for the reliving angle for the rick. The 3/4" anchor bolts are a single bolt spaced at 16" O/C. The brick span/relieving angle span is about 13'-9" and the height of the brick is 15'-0". I believe that I would have to see if the angle can support the weight of the brink then test the connection of the weld. Then check the shear bearing (which I am not sure if its the shear) of the plate which I am proposing to change to a L angle if the plate isn't sufficient. The height) of the 4"x3/8" plate is 2'-3". And lastly I would have to test the 3/4" anchor bolt capacity and breakout from the concrete. I am just not too familiar with calculating breakout when its on the X-plane, I am more familiar with columns and other types of embedment.

Thank you.

 

[JedClampett]

Several comments:
[ul]
[li]You have a 6 inch leg horizontal, yet the dimension to the outside of the brick is 9 inches.[/li]
[li]What is the edge distance for the 3/4 inch bolts to the slab bottom?[/li]
[li]What size welds?[/li]
[li]Your 3/8 inch plate will see some significant bending out of plane. Deflection might also be an issue.[/li]
[li]I routinely use 8 x 8 x 1/2 inch angles in this kind of design. Your horizonal leg might have a bending issue. It's a little cantilever.[/li]
[/ul]
You should move this to the "Structural engineering general discussion" page.

 

[MaxMedic]

I just noticed that the reveling angle is only 6", I agree on using an 8" angle.

It looks like the bolt is 4.5" to slab bottom and the thickness of the slab is 9".

1/4" weld typical.

Agreed, may want to consider using an angle instead of a plate.

 

[MaxMedic]

How do I move the thread?

 

[phamENG]

Report your original post and in the comments ask the mods to move it.

Any reason you can't align the relief angle with the floor? That's how it's usually done. Even if you us an angle, you'll still be dealing with a pretty good moment and you will see some out of plane deflection.

 

[MaxMedic]

The relief angles need to sit on top of the windows to catch the brick.
Can always pose to put an angle above the windows and at the slab.

 

[phamENG]

That would probably work better - unless your windows are continuous. As long as they're "normal" windows - 5 to 8 feet wide or less - then loose lintels at the windows and reliefs at the floor levels will be the way to go.

 

[masonrygeek]

The term really should be "shelf angle" and not relieving angle (at least in the US). These angles don't really "relieve" any weight and are only used to create a horizontal expansion joint in the brickwork. An article on the design of shelf angles can be found in this article in Structure magazine:

https://www.structuremag.org/?p=219.

 

[MaxMedic]

They are normal approximate 6’-0” windows

 

[JLNJ]

Draw yourself a free body diagram. Where do the forces come from? Where do they go?

It looks like someone intends the vertical load from the brick to be carried into the slab. How does the load get there. The slab edge and brick center is mass don’t line up, right? So what happens? How does this system work?

Worry less about weld checks and worry more about understanding the load path.

 

[MaxMedic]

Thank you so much everyone for your inputs.

 

[bones206]

There are some proprietary products out there that are quite good. Here is one that I am familiar with.

https://ferocorp.com/products/fast-thermal-brackets/.

They will do the all engineering for you if you don't feel confident doing it yourself.

 

[EcoGen]

Here's my two cents:

[ul]
[li]You should definitely use an angle instead of the plate to hang the horizontal angle from.[/li]
[li]To stabilize the whole thing from rotation you should also consider a diagonal kicker angle attached back to the bottom of the slab since it is hung over two feet.[/li]
[li]If you're using post installed epoxy anchors, HILTI PROFIS software can do all the concrete breakout checks for you.[/li]
[li]Like other people mentioned you'll probably be better off using a loose lintel angle above the window and a separate shelf angle at the slab to avoid all the additional steel components.[/li]
[/ul]

 

[dik]

and move the fastener to 3" or 4" from the TOP of the slab. Added: See if a 3/8" angle works better and leave a gap at the underside of the angle for movement. Clay brick expands with time and concrete shrinks.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[dik]

I couldn't find a detail; I've encountered lots of them where there is a plate secured to the slab edge with headed studs. Two angles are welded to provide adjustment; these are located at 3' or 4' and the shelf angle is attached to this. Works well... good thermal isolation and adjustable. Only caution is that it's HDG and field welded.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[BAretired]

See below.

BA

 

[dik]

or mine above... use an L4x4... and thermally broken. I've sealed dozens of shop drawings with this connection... I have an SMath program for design. It's really common here and variations are used to support SOG at entrances. There could be 2 studs, spaced horizontally with 3" cover to the top of the slab.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[BAretired]

Yes dik, your detail is probably better.

BA

 

[dik]

The more interesting question is where the brick load is applied to the shelf angle.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[dik]

Not my detail, it's one that I've checked and designed 50-100 times... my current work is sealing shop drawings, and I'm nearly at 600 projects for the last 2 years.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik