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RE: LGSS (Light Gauge Steel Studs) Need design example

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Ernie and Tim,
Thanks for your responses. The same problem that Ernie is having is the
reason I submitted my request. I have been trying to follow the guidelines
established in; "Commentary on the Prescriptive Method for Residential
Cold-Formed Steel Framing" Second Edition.
Of course this follows thier published Prescriptive method, but offeres the
supporting engineering calculations for the published recommendations. As
Ernie pointed out, the analysis is very lengthy and difficult to follow.
Dean Peyton PE of Anderson-Peyton, Federal Way Washington is the president
of LGSEA and cautioned me to check the compression studs for buckeling. He
was adament that this was required in the 1997 UBC even though he did not
understand why ICBO inserted this section.
Previously, I have been designing shear walls using 16 or 18 gauge studs and
doubling the studs at each end of the wall panel. Dean explains that the
thicker gauge studs actually works against the wall in cyclic (I believe he
was refering to cyclic) action. He explained that with the thicker studs
there would be no movement allowed for the screws in the stud flange and
this would cause the screws to shear off before the studs failed at the
rated APA values in their report #154. Therefore, it was an advantage to
keep the studs lighter gauge and flexible, but also important to design the
compression studs for buckeling in accordance with the provisions of the '97
UBC.
Any comments????? At this point I am going to double up 20 gauge studs for
low value shear walls and go back to 16 or 18 gauge studs for higher
shearwalls until I can be sure how to attain a valid capacity.
Just a thought. If I were to create a Mathcad analysis following the
provisions in the prescriptive method (the long lengthy version) would if be
of any interest to anyone else? If it would, I will spend the time and
donate it to the list. Let me know, you would only need to obtain the
section properties and radius's of the manufacturer you are using (unless
there is some standardization).

Dennis Wish PE