Shearwall With Force Transfer Around Opening

[nrguades]

I have been reading old treads regarding Force Transfer Around Openings of Wood Shearwalls, but it seems like there were varied interpretations of where the holdowns will be located, whether at the ends every shearwall segments or at the ends overall wall width. I just wonder if there are already some clear explanations or answers regarding this issue now.

 

[WillisV]

If this method is performed hold-downs are only needed at the ends of the overall wall, not at both the points adjacent to the opening and at the wall ends.

 

[csd72]

http://www.awc.org/Publications/download.html

Look near the bottom under perforated shearwalls.

This is one method, the other is to ignore the section with the window and treat it as several different shear walls each with their own tie down.

 

[msquared48]

I agree... With the perforated shearwall anslysis, you are essentially designing a moment frame, where the holddowns would only be needed at the extreme ends of the frame.

Mike McCann
MMC Engineering

 

[nrguades]

After posting this thread, I tried to search new publications about this issue and I was able to get good explanations from the following seminar notes based on IBC 2006 and the CBC 2007.

http://www.woodworks.org/files/PDF/..._and_Wind_Design_-_K_Beebe_APA_-_Jan_2008.pdf

This shows a comparison and an example of the three methods. The Segmented, Force Transfer around Opening and Perforated Shearwall.

But on the Force transfer around opening example, the segment adjacent to the door is not used, but this segment was used on the other methods. This make me wonder, if considering I have a wall with 3 small doors in series (not windows) , can I still use force transfer around opening with holdowns at ends of the overall width only?

Or maybe a more straightforward question is whether the Force transfer around opening method having holdowns at the ends only is also applicable to door opening?

 

[DHambley]

nr, Since the highest stress is at the openings, I would calculated the actual shear at each opening. At the extreme case, a high door for example, the top only acts as a collector and can handle no verticle shear. In this case, straps may be needed at the openings, depending on the actual shear load.