Perforated Shear Wall Anchorage Between Ends
Perforated Shear Wall Anchorage Between Ends
(OP)
We usually do a couple 3 story wood framed apartment buildings a year. I have always designed these with segmented shear walls and had hold downs at pretty much every corner and wall opening. Recently contractors have been complaining about the cost of this system. To limit the amount of hold downs I am starting to look at designing the shear walls as perforated. I have found some design examples to work through and am trying to get comfortable with this system. The only issue I have so far is trying to resolve the uplift force between hold downs. I am not asking about hold downs at the ends of the wall. It looks like I have to design the bottom wall plate to transfer tension and shear so that if I have 300 PLF at the top of the wall I need to specify a connection to transfer this load in shear and tension. This seems pretty easy at the ground floor but I can't find a good way to do this at the second and third floors. Am I missing something? How do you transfer this load?
RE: Perforated Shear Wall Anchorage Between Ends
3 story apartment, I would be using shrinkage compensating tie downs instead of holdown anchors. If you don't make sure you account for shrinkage in your drift calculations.
RE: Perforated Shear Wall Anchorage Between Ends
Nah, it sounds at though you've got it figured out. This document describes the phenomenon and includes some tension tie down details: Link
This method is another option to be considered: Link. It can negatively affect constructability, however, depending on what is being proposed in terms of prefabrication etc.
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: Perforated Shear Wall Anchorage Between Ends
RE: Perforated Shear Wall Anchorage Between Ends
RE: Perforated Shear Wall Anchorage Between Ends
As far as I can tell, you're not missing anything. It's a lot of load and a connection that essentially bypasses the sill plate may well be the way to go.
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: Perforated Shear Wall Anchorage Between Ends
KootK - Do you reduce the uplift load by including dead weight of the wall?
RE: Perforated Shear Wall Anchorage Between Ends
I do indeed.
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.