Wood Shear Walls on CMU Walls
Wood Shear Walls on CMU Walls
(OP)
I have a fairly regular shaped two story homes being designed with the 1st story as CMU and the 2nd story 2x6 framing. The roof is a 7/12 gable and the upper floor shear walls running parallel with the ridge have windows/doors pretty much everywhere. All my aspect ratios for my segments along these walls are greater than the allowable limits. The whole second floor pretty much is open and none of my interior walls line up with walls below to be used for shear. I ran some numbers using the APA force transfer around openings calculator but I am getting very high shear wall deflections as I expected. What would be the best options to move forward?
RE: Wood Shear Walls on CMU Walls
RE: Wood Shear Walls on CMU Walls
RE: Wood Shear Walls on CMU Walls
RE: Wood Shear Walls on CMU Walls
RE: Wood Shear Walls on CMU Walls
Since you're already block on the bottom, would there be any sense in running a section of it up to the roof as second story, perforated shear wall? That would probably wreak havoc on the exterior wall detailing of course.
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Wood Shear Walls on CMU Walls
RE: Wood Shear Walls on CMU Walls
If wood is not an option I see multiple other options:
Simpson strongwalls are an option but I feel like builders hate them. It's a pain to get the anchors to work out and the contractors never install them right in the end.
Cantilever steel columns may work if your loads are light.
Cantilever reinforced concrete columns which are infilled with CMU.
A fully welded HSS frame is usually what we use. It's all site built here and fairly easy to build. The builder's usually try to avoid steel at all costs due to the extra trade.
RE: Wood Shear Walls on CMU Walls
Yes I agree with the simpson walls in the field but they make it really really easy to spec out from a designers standpoint. When using cantilevered steel or RC columns what is typically used to transfer the lateral loads to the next column/segment or does 1 typically transfer the entire load? Sorry, I typically only deal with wood and a little CMU so its just a bit out of my wheelhouse.
RE: Wood Shear Walls on CMU Walls