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h2. How is a frame assigned a sidesway-uninhibited condition, rather than sidesway-inhibited?

*Extended Question:* Further, should I use the effective length factors automatically calculated through [SAP2000|sap2000:home]? K = 1.0 for all members under any configuration, which does not seem accurate. Should K factors be input manually?

*Answer:* {new-tab-link:http://www.csiberkeley.com/}CSI{new-tab-link} Software implements a rigorous process to determine K factors. A full description is available in the {new-tab-link:http://www.csiberkeley.com/}CSI{new-tab-link} _Steel Frame Design Manual_ (Help > Documentation > Design > Steel Frame Design > Design Algorithms > Element Unsupported Lengths > Effective Length Factor).

A notable point mentioned in this section (pages 11-14) is that K-factor calculations are based on the assumption of uninhibited sidesway. For other cases, K factors should be specified by the user. Users should always, however, use engineering judgment to evaluate the accuracy of K factors calculated by computational tools. Any discrepancy between the unbraced properties modeled and the actual design intention may lead to inappropriate design.

Automatically-generated K factors may be overwritten for individual members using the Overwrite option under Stress Check Information, as shown in Figure 1:

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!Steel_frame_design_overwrites.png|align=center,border=0!

{center-text}Figure 1 - Frame-property overwrite{center-text}


h1. See Also

* [kb:Sway and nonsway conditions] article