gypsum wallboard shear wall capacity using undersized fasteners
gypsum wallboard shear wall capacity using undersized fasteners
(OP)
Anyone know of prescriptive or analytical methods for determining the reduced values in shear wall capacity when using either undersized fasteners or larger spacings shown in the IBC tables? The sheathings in my case (analysis of existing structure) are gypsum wallboard and gypsum sheathing.
Also, I have 2x4 stud spacing of 12"oc in many areas.
One school of thought is to totally discount the shear capacity of the wall (since there are no published capacities), but this is not realistic. Even inadequate fastening of sheathing provides SOME capacity.
I'm fairly positive that the reduction is NOT linear based on nail cross-section, nor penetration.
All ideas are welcome.
Thanks,
Doug
Also, I have 2x4 stud spacing of 12"oc in many areas.
One school of thought is to totally discount the shear capacity of the wall (since there are no published capacities), but this is not realistic. Even inadequate fastening of sheathing provides SOME capacity.
I'm fairly positive that the reduction is NOT linear based on nail cross-section, nor penetration.
All ideas are welcome.
Thanks,
Doug






RE: gypsum wallboard shear wall capacity using undersized fasteners
I would be careful, though, and will be interested in hear what others say.
RE: gypsum wallboard shear wall capacity using undersized fasteners
1st of all, this structure was designed under the UBC97 code. I am analyzing the lateral capacities, not designing.
2nd, I can't get too specific (for legal reasons) other than the fasteners used are less than the sizes called for in the tables, their lengths are shorter, AND the spacings are larger.
What would be most helpful would be references or methods to "defend" our position that the shearwalls, as constructed, DO have a quantifiable capacity of XXX plf -not zero.
Doug
RE: gypsum wallboard shear wall capacity using undersized fasteners
RE: gypsum wallboard shear wall capacity using undersized fasteners
This will answer many of the obvious questions.
Dick
RE: gypsum wallboard shear wall capacity using undersized fasteners
nerdse, the test panel would be a very viable alternative. but comparing with published results would involve HAVING published results using indadequate connections.
as far as a jury understanding the tested panel's capacity versus a bunch of math ... I'd still like to use math, at least for corraboration.
thus, if you have ideas or references to DO the math, that would be most helpful at this point.
Doug