Shear strength mechanism in CMU walls for out-of-plane loading?
Shear strength mechanism in CMU walls for out-of-plane loading?
(OP)
For out-of-plane shear strength in reinforced CMU walls per ACI 530, does it matter if the shear is checked at a pour joint or not? It doesn't say anything. It seems like this would affect the shear strength.
For example, at the base of a cantilevered CMU wall, can I use the ACI 530 shear strength equations, even though you are only relying on friction and/or grout bond for shear strength?
For example, at the base of a cantilevered CMU wall, can I use the ACI 530 shear strength equations, even though you are only relying on friction and/or grout bond for shear strength?






RE: Shear strength mechanism in CMU walls for out-of-plane loading?
RE: Shear strength mechanism in CMU walls for out-of-plane loading?
RE: Shear strength mechanism in CMU walls for out-of-plane loading?
Read the commentary for 2.2.5 for Shear.
It recommends using section 2.2.5.2 for limiting out of plane shear.
There is also nice flow chart for shear design in the commentary.
RE: Shear strength mechanism in CMU walls for out-of-plane loading?
RE: Shear strength mechanism in CMU walls for out-of-plane loading?
That is for unreinforced masonry. They have separate shear provision for reinforced masonry. For walls, I'm not sure why there should be a difference, unless shear reinforcement in provided.
RE: Shear strength mechanism in CMU walls for out-of-plane loading?
Right, but the pour joints in reinforced CMU walls are less frequent, maybe 5'-0 on center. I can't imagine that the shear strength at a pour joint would be the same as away from the joint.
RE: Shear strength mechanism in CMU walls for out-of-plane loading?
It's been a few years since I have designed masonry....just trying to help.
Sorry
RE: Shear strength mechanism in CMU walls for out-of-plane loading?
The vertical bars in a reinforced CMU wall are generally sized based on out-of-plane bending. If you wanted to rely on the dowel action or shear-friction mechanism, wouldn't you need to up the size of the bars accordingly?
RE: Shear strength mechanism in CMU walls for out-of-plane loading?
The flow chart doesn't address the presence of a pour joint or not in reinforced masonry. Thanks.
RE: Shear strength mechanism in CMU walls for out-of-plane loading?
I am sorry to waste your time.
RE: Shear strength mechanism in CMU walls for out-of-plane loading?
[thumbsup2]
RE: Shear strength mechanism in CMU walls for out-of-plane loading?
BA