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Column K factor.

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We designed a tilt-up building with metal deck for roof  (no zonolite or 
structural concrete fill). The building is approximately 200'x200'. Framing 
consists of OWSJ supported on WF steel girders.. The girders cantilever about 
4 ' over columns with drop-in beams at alternate bays.Connection is with 
shear plates. Girders have full height stiffners on both side of web at 
column supports and bolted with 4 bolts to the cap plate. OWSJ have slip 
connection at bot. chord to allow for free deflection of the joists. The 
columns are spaced at 40' on center, both direction,  and are HSS 6x6x0.5 X 
22' tall. The framing, including columns were designed using RAMSTEEL 
programme (over kill) with eccentricites included in in both axis.This is a 
VA non-essential facility in West LA. Building and is all complete and ready 
for TI improvements.
SO FAR SO GOOD. We now have a Very Senior VA engineer from Washington (shall 
remain name less for now) telling us that the columns should be designed per 
AISC Table C-2.1 column (f) (Page 5-135) with K=2. i.e with pin at ground - 
Rotation fixed and translation free at top.
We have designed the columns as pin-pin with K=1. We, very strongly, do not 
agree with his assesment but because of his high position we cannot convince 
VA that our design is adequate.
We thought this would make an intresting topic for discussion.
Thanks to all, in advance.
Kulwant Brah