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["Carter, Charlie" <carter(--nospam--at)aisc.org>]

>Josh Plummer wrote:

>Just wait until you try to make sense

>of the new chapter C provisions (Stability

>Analysis and Design)….

 

Those of you who do advanced analysis now will find that the Direct Analysis Method in Appendix 7 results in a significant simplification in how one can address stability effects directly in the analysis. It is explained in quick summary form on the Basic Design Values cards, along with the two other methods provided (effective length method and amplified first-order method). One can often take K = 1 for column design, even in moment frames, when these methods are used.

 

The Basic Design Values cards also have a great little nugget for those of you who prefer a simplified analysis. The Simplified Method allows you to select a simple multiplier that you can apply to the results of a first-order analysis. You will pick the multiplier out of a table based upon the drift limit you’ve selected for your building and the ratio of gravity load to lateral load. This simplified method is derived from the effective length method and has a range where K can still be taken equal to 1 for column design, even in moment frames.

 

I think if you look at the summary provided in the cards, you will find that analysis requirements for steel buildings are now the simplest requirements out there for any material.

 

Charlie