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Distinguished Contributor
Tuctas
Posts: 185
Registered: ‎10-10-2012

Vertical eccentricity of columns

840 Views, 9 Replies
12-27-2012 01:56 PM

  When we have a (R/C) column upon which it is placed with vertical eccentricity a column with smaller section dimensions, the usual way is to define manually an artificial rigid member between the C.W of the two members (since it isn’t generated automatically from the program) with high values of basic and mechanical properties.

  Is there any chance for that kind of modeling to be generated in a “less manual” way? For instance, if we try to define an internal node along the beam that ends to that column but in a point that belongs to offset length that has been already defined between beam and column (see attached screen capture), would that modeling be precise?

 

  And also a question that concerns the manual way: what kind of magnitude of values should we assign to properties of that artificial rigid member in order not to face numerical problems? (I am getting a message “Instability of type (2) detected at node” of rigid member).

 

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Distinguished Contributor
Tuctas
Posts: 185
Registered: ‎10-10-2012

Re: Vertical eccentricity of columns

12-27-2012 10:21 PM in reply to: Tuctas

  I forgot to mention that usually we are not able to define a rigid link (instead of a rigid member) because in that case we are not able to include that node to the diaphragm of the corresponding floor (diaphragm=rigid links and a node cannot belong to more than one master node)..

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Rafal.Gaweda
Posts: 5,207
Registered: ‎04-26-2010

Re: Vertical eccentricity of columns

12-27-2012 11:05 PM in reply to: Tuctas


  And also a question that concerns the manual way: what kind of magnitude of values should we assign to properties of that artificial rigid member in order not to face numerical problems? (I am getting a message “Instability of type (2) detected at node” of rigid member).

 


I usually define them with such data:

 

StiffSectionData.SetValue I_BSDV_AX, 100000000
StiffSectionData.SetValue I_BSDV_IX, 100000000
StiffSectionData.SetValue I_BSDV_IY, 100000000
StiffSectionData.SetValue I_BSDV_IZ, 100000000

 

 



Rafal Gaweda