Simple Colum Effective Length Factor K 1

[fishy]

We have a basic load bearing tilt-up concrete wall warehouse with diaphragm roof deck and the walls taking shear. The roof is conventional open web roof joists and girders. The girders seat on top of the pin-pin columns. I am trying to justify the common use of a K factor of 1.0 to select the column size for support of the axial loads. The columns have roof steel members framing in on all 4 sides. I am not sure how to apply the definitions of braced and unbraced frames in AISC. Our columns will not be braced but can the frame be considered braced by the deck transfer to the shear walls?
If so then the K factor can be 1.0.

 

[JAE]

You have a braced condition as the lateral stability of the building does not depend upon the columns in bending to resist the lateral drift. Thus, the k factor should be no smaller than 1.0.