ACI 318 App D for CMU

[Lion06]

If you have a bearing plate for a CMU wall that has some tension and moment on it, is it reasonable to design the anchor embedments using ACI 318 APP D? ACI 530 doesn't have an "APP D" or anything comparable, does it? Would you just use f'm in place of f'c?

 

[Teguci]

ACI 318 is for structural concrete only. Appendix D was put out by the PCA and includes testing results from concrete systems (they even used European test data for their results).

For masonry, I would suggest going to the anchorage company and use their recommended numbers for the anchors.

 

[UcfSE]

ACI 530 has equations for anchor tension and shear. Have you tried those?

 

[Lion06]

Those equations (in ACI 530) don't account for edge distances or direction of load. Does anyone see that as an issue?

 

[Gumpmaster]

They do allow for edge distances. You have to truncate the projected failure cone where it intersects with an edge or another failure cone.

I haven't read it yet, but the ACI 530-08 apparently changes the anchoring equations.

 

[ronster]

In 30 years of engineering I have never seen a bearing plate in a masonry wall with moment on it. Are you designing the beam as a fixed end or is it resisting torsion? Or is this a column base plate in a moment frame?

Depending on the magnitude of the tension force and assuming it is pulling out from the wall then I might consider an alternated method of transfering that force then 2 bolts that are near the edge of the wall. If the beam is pulling on the wall then what is bracing the wall?

 

[Lion06]

It is a header for a hydraulic door. When open the header has a lateral load on it which creates torsion in the HSS. The lateral load is pretty significant (almost 1k/ft) and the associated torsional reaction is 2.5 k-ft. This also occurs at the end of a 8" CMU wall.

 

[Lion06]

Not to sound like a complete dope, but I am looking at ACI 530-05 and I can't find any equations for shear loads which correspond to small edge distances.
I see equation 2-5, and the note in 2.1.4.2.3 that says "Where lbe is less than 12 db, the value of Bv in Eq. 2-5 shall be reduced by linear interpolation to zero at an lbe distance of 1 in."
That deals with embedment, though, not edge distances. I do see something in the commentary (on page CC-26 and CC-27, but it isn't very clear about how to adjust for edge distances).