sway and non-sway moment magnifier and K factor 1

[mscme]

I have been trying to model a 6 story reinforced concrete building and using ETABS to design the columns. I did determine that all the stories are sway and made the frame sway ordinary in the overwrites box. However it does not calculate the sway moment magnifiers, i did check the non sway moment magnifiers and they seem right.

I also checked to see if ETABS calculates the k-factor. I noticed that its default value is 1 (which would be conservative for a non-sway frame however ACI says the min is 1.2). I did a quick hand calc and noticed that the k-factors for my building should be between 2-4.

Is there a setting or option that has to be turned on for ETABS to calculate them?

 

[WillisV]

Read the ETABS documentation for column design - this is all explained in there (for instance see pages 2-7 and 3-12 of the "CFD-ACI-318-05.pdf" file). Sway moments are assumed to already be magnified (you must run a P-delta) and non-sway slenderness magnifiers are conservatively based on a K of 1 which can be overwritten by the user).