Column classification: Sway or not sway 2

[johnbridge231]

Hello,

I would be grateful if somebody could tell me how SAP2000 classifies a column as sway or not sway. As known, this is needed for the calculation of effective lengths. Does is check the existence of braces somewhere in the model in that direction, does it perform a displacement criterion internally, or anything else?? The manual does not contain such information, it only describes the way SAP2000 calculates the effective buckling length, assuming that the examined column is sway or not.

Thank you.

Analysis and Design of arbitrary cross sections
Reinforcement design to all major codes
Moment Curvature analysis

http://www.engissol.com/cross-section-analysis-design.html

 

[Jatfuentes]

Hi,
You need to say to SAP if the column is restrained to lateral movement or not. If your column is braced, then is not sway, if not , is sway. But you need to analize the the structure if it can move or not from the point of view of engineering, SAP do not make this kind of decition. Test yourself with a simple two column frame, first braced and then unbraced and see what SAP does.

 

[johnbridge231]

Oh my god, you did not get me at all! SAP apparently automatically adjusts the effective length factors to be gretaer or less than 1, for example 0.5 or 3.1 etc.
Since SAP introduces values greater than 1, it means that it does a frame classification internally and sometimes suggests length factors that correspond to sway frames. All I ask is how it makes that decision. I think you have now understood my question.

Analysis and Design of arbitrary cross sections
Reinforcement design to all major codes
Moment Curvature analysis

http://www.engissol.com/cross-section-analysis-design.html

 

[ayelamayem77]

dear johnbridge231 ,

i think the following link will be very helpful

http://www.structural-experts.com/showthread.php?tid=765

 

[johnbridge231]

Dear ayelamayem77,

Thank you very musch, this is what I was looking for.

Analysis and Design of arbitrary cross sections
Reinforcement design to all major codes
Moment Curvature analysis

http://www.engissol.com/cross-section-analysis-design.html

 

[ayelamayem77]

Dear johnbridge231,

you are most welcome , i wonder if you can help me to solve the following problem

link:

http://www.eng-tips.com/viewthread.cfm?qid=339526

thanks in advance