Lintel Detail - Brick and Masonry - Torsion on Lintel

[RFreund]

I know there was a discussion on this in the past (trying to find this).
The situation is - where WF lintels are specified centered in the CMU wall and a plate extends to support the brick. The WF or Tube can be sized for torsion etc, but then the torsion needs to be taken out at bearing points into the masonry wall.

I've attached a quick sketch/detail that extends the plate below the brick, into the brick, to help resist this torsion. Is this a bad detail?
What other details are typically used when the torsion becomes somewhat large (what is somewhat large)? I suppose kickers could be used as well but they would need to restrain the moment/torsion.

EIT

http://www.HowToEngineer.com

 

[EngineeringEric]

I actually am working on this same thing right now so i will let you know what we come up with. As for the attached detail i would be leery of putting that load into the brick, especially depending on the size of the opening and the presence of control joints.

I would typically design the beam to handle the torsion, and the bearing to handle it as well. analyze the bearing and you may find that that the outside edge has lots of compression and the inner has less (not uplift) due to the dead weight of the system... then design the bearing plate and block accordingly... but may not work depends on the condition.

 

[msquared48]

Depending on the framing levels, I usually try to take out the torsion with lateral knee braces or kickers connected to web stiffeners with at least two bolts.

You could also use a tube section for the lintel beam instead of a W section.

Mike McCann
MMC Engineering

 

[XR250]

I see it done commonly with and without kickers. I don't know how they are getting the numbers to work out without kickers unless they use a tube section and it has something to resist its torsion the the ends.
Gotta love brick veneer - Not!

 

[haynewp]

It looks like CMU is backing the brick. You can put in deformed bar anchors welded to the top of the WF beam and extending into vertically grouted cells at each end of the beam. Weld the bottom of each end of the beam to a bearing plate.

We used to put it DBA's welded along the top of the WF beam also and extending into grouted cells in the CMU above.

 

[RFreund]

Thanks for the input, I've had similar thoughts as above.
I was thinking that the plate is only carrying the weight of the brick so extending it to bear on itself would be similar to a loose angle. It seemed simple enough to do, but maybe not. I would prefer kickers but it seems that so frequently this is not option due to ceiling elevation.

EIT

http://www.HowToEngineer.com

 

[JAE]

If there is something to kick against, we sometimes use kickers.

For many other applications we do what haynewp describes and use the wall above (its flexural strength and stiffness) to take out the torsion by linking the lintel to the wall.

Taking out the torsion at the beam support doesn't work well with WF beams as they have little torsional stiffness and unless you have a column at the end sufficiently connected to take out the torsion I hate to use the opening "jamb" sections of wall to take all the twist. - better to take it out along the length.