Shear Wall with Openings analysis

[KeySol]

Recently I have been doing research into the use of shear walls opening in residential wood design. We have both the 2006 Structural/Seismic Design Manual Vol 2 by SEAC, and the Breyer Design of wood structures book sixth edition. Both of these gve an example of doing shear walls with openings design. My question is in regaurds to the difference in their designs. Both are "rational" and give similar but different reults. I am wondering if there are any onpinions on which method is more commonly used.

Any thoughts and remarks would be greatly appreciated.

 

[MiketheEngineer]

You might want to check out the IBC2006 and IRC - they both have examples..

 

[OldPaperMaker]

KeySol,
1.I always use the Segmented Shearwall method, which is explained in Section 6a of the 2006 IBC Structural/Seismic Design manual, Vol 2. I know how this works and I can rationalize using it all of the time.
2.The Force Transfer Around Openings, explained in Section 6b is a major pain in the ass to work through. I never use this. I don't like using a similar process when I have a diaphragm with a large hole in it.
3.The Perforated Shearwall Method, explained in 6c can't be used if the shear is greater than 490 plf (per IBC 2305.3.8.2.1, #2)so I don't use this method. This method uses holdowns only at the ends of the line of shearwalls so it might save a bit of money on the hardware. I think that this method is a result of some large scale tests of buildings. Generally, this Old Dog doesn't think that the new trick is worth the time to understand & start to use something new.
4.I feel the same way about some of the "stuf" that has been added to our bag of new tricks in the 3 year code change cycle. But, the codes don't give us the option to pick and chose so I just grump about it in forums like this and try to understand the codes.
Regards

 

[brada]

Keysol, the design of a wood wall frame with force tranfer around openings is a useful tool all though it is a bit time consuming. It is pretty easy to layout a spreadsheet to crunch the numbers. Follow the example in "2006 IBC Structural/Seismic Design Manual 2, SEAOC. p. 28.
Does anyone have an example for when there are two openings in the wall?

 

[KBVT]

The perforated shear wall method was based on full size testing, I believe at the Forest Products Society Laboratory. The limitation on 490 plf represents a seismic capacity, so you can apply a 1.6 multiplier to achieve a relatively high shear wall capacity in wind controlled designs. You pay with higher unit shear values due to the lack of localized uplift resistance at the tension side of each shear wall segment. The design around openings is challenging in terms of looking at each individual piece of the wall and adding hardware, i.e. straps, above and below the opening to transfer the tension. I use perforated design at the exterior of my buildings often and have found it to be very useful in reducing the amount of anchorage hardware I have to specify.

 

[faromic80]

Where can I find an example of that kind of design?