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Assigning Stories

24 REPLIES 24
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Message 1 of 25
Tuctas
2489 Views, 24 Replies

Assigning Stories

   When for some elements that are out of the height of a storey we try manually to change the storey in which they were initially defined, an error message appears: “The element is defined on a storey different from the assigned one“ and after that we are not able to run the analysis.

  Is there a way that we can normally assign a storey to elements that are out of the height of it?

  (In the attached example i firstly defined a storey and then I manually changed the storey of some elements from the inspector dialog box).

 

24 REPLIES 24
Message 2 of 25
Rafal.Gaweda
in reply to: Tuctas

Geometry \ Stories \ Assign Manually



Rafal Gaweda
Message 3 of 25
Tuctas
in reply to: Tuctas

  The result is the same: the stories are defined (and modified) o.k but the analysis is interapted.

Message 4 of 25
Rafal.Gaweda
in reply to: Tuctas

Send me model



Rafal Gaweda
Message 5 of 25
Tuctas
in reply to: Rafal.Gaweda

  Although i cut my model, i neglected-deleted different kind of a atributes that may cause a big space and then i ziped it, it is still a large file so i am not able to send it (>1.60MB).

Message 6 of 25
Rafal.Gaweda
in reply to: Tuctas

Post the link to file generated by www.filemail.com or www.wetransfer.com service



Rafal Gaweda
Message 7 of 25
Rafal.Gaweda
in reply to: Rafal.Gaweda

This error message is related to geometrical check of objects assigned stories.

Stories in robot are not architectural stories (just a group of elements with “story” property). Robot produces calculation results for stories

so if geometrically elements are wrongly assigned it may lead to wrong stories results and error message is reported.

So if you do not care about stories results just turn off automatic verification in job preferences.

 

st2.jpg



Rafal Gaweda
Message 8 of 25
Tuctas
in reply to: Tuctas

  Thank you Rafal for your answer.

 

  I can’t say that my question is fully covered because my intention was to use the results of stories (otherwise I wouldn’t make the question..).

   I suppose that it is the way that Robot works as concerns the definition of stories and we can’t include members out of the height of a storey. In the attached example there is not any “wrong” assignment, members belonging to that balcony should belong to the storey below and not to the upper one.   

  For example, if someone wants to detect the change of mass along the height of a structure (as it is asked sometimes in EC8) the right way is to include these (“wrongly assigned”) members in to the storey below and not in to the above one. 

Message 9 of 25
Artur.Kosakowski
in reply to: Tuctas

What about replacing the 'red' part of the model with masses (loads converted into masses)? This part doesn't look like an important structural one Smiley Happy

The story approach has got some limitations mainly because of the way of calculating results for them.

 

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.



Artur Kosakowski
Message 10 of 25
Tuctas
in reply to: Tuctas

  Hi Artur,

 

  Yes, manually the user can do some "tricks" to consider what he wants, i was wonderring if though the definition of stories it could be automatically done.

 

  One more question: What if the option that is shown in the attached screen capture is unchecked? What does this optiom really mean? (i thought maybe it could do what i was trying with those "red" members but it didn't).

Message 11 of 25
Artur.Kosakowski
in reply to: Tuctas

It removes the assignment of the story from objects that do not 'meet' the geometrical limits of the story they are assigned to.

 

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.



Artur Kosakowski
Message 12 of 25
Tuctas
in reply to: Artur.Kosakowski

  So if we have checked this box, the elements that do not meet the geometrical limits of a storey are ignored during the calculations of different kind of values of stories (in other respects the calculations are being carried on normally)?

Message 13 of 25
Tuctas
in reply to: Artur.Kosakowski

  Please add two more questions (in order to clear out how Robot works in these cases).

 

  If we don’t make any manipulation but we define stories with the “normal” way, so these “red” elements will be included in the above storey:

 

  1. In which way does Robot calculate the averaged storey displacements in such case?

 

  I mean that if these “red” elements belong to the above storey, how exactly the “average displacement of the gravity center of the storey slab” is calculated? (help topic: http://docs.autodesk.com/RSA/2013/ENU/index.html?url=filesROBOT/GUID-890C3B44-F7EE-4BB1-8C39-19F445B...).

  Are the nodes that belong to those “red” elements being considered in the slab that they physically belong or not?

 

  2. The calculation of  Center of gravity of floor slab (F) of the storey below does it takes into account these “red” elements or not?

 

Message 14 of 25
Artur.Kosakowski
in reply to: Tuctas


  So if we have checked this box, the elements that do not meet the geometrical limits of a storey are ignored during the calculations of different kind of values of stories (in other respects the calculations are being carried on normally)?


Correct. You can also force Robot to calculate them as being assigned to the story below by setting the verification to none (Job Preferences > Structure Analysis) ignoring errors and warnings but then the check of the correctness of the results is entirely in your hands.



Artur Kosakowski
Message 15 of 25
Artur.Kosakowski
in reply to: Tuctas


 

  If we don’t make any manipulation but we define stories with the “normal” way, so these “red” elements will be included in the above storey:

 

  1. In which way does Robot calculate the averaged storey displacements in such case?

 

  I mean that if these “red” elements belong to the above storey, how exactly the “average displacement of the gravity center of the storey slab” is calculated? (help topic: http://docs.autodesk.com/RSA/2013/ENU/index.html?url=filesROBOT/GUID-890C3B44-F7EE-4BB1-8C39-19F445B...

  Are the nodes that belong to those “red” elements being considered in the slab that they physically belong or not?

 

The average displacement of the story is the weighted displacement of the center of the gravity of the ceiling of the story where the weight is the mass of the surface elements of the ceiling therefore it does not depend of the columns from the above or below.

 

  2. The calculation of  Center of gravity of floor slab (F) of the storey below does it takes into account these “red” elements or not?

 

No, it does not.

 


 



Artur Kosakowski
Message 16 of 25
Tuctas
in reply to: Artur.Kosakowski

 Artur, thank you for your answers.

 

  I made an investigation between 3 cases:

  1st case, the results came out by leaving the program to define stories “normally” without any manipulation,

  2nd case, the results came out by neglecting the “red” elements from any storey (this can be done not by using the options of the window “Assign Geometrically” but through the option “Advanced options” of the window in which we normally define stories),

  3rd case, the results came out by assigning manually to the “red” elements the 1st storey.

 

  There are similar results between 2nd and 3rd case (except of course the value of mass at the ceiling of the 1st floor).

  Between 1st case and 3rd case there was a difference at the coordinates of the Center of gravity of 2nd (!) storey slab and thus in the average storey displacements (and so the drifts). I cannot explain it..

  Between all cases there are differences in the results of modal analysis (periods, relative masses e.t.c)!? (Although, the total mass was equal). Modal analysis should not get bothered by any kind of manipulation about stories..

 

Message 17 of 25
Artur.Kosakowski
in reply to: Tuctas

Send me these 3 files please.



Artur Kosakowski
Message 18 of 25
Artur.Kosakowski
in reply to: Tuctas

  Between 1st case and 3rd case there was a difference at the coordinates of the Center of gravity of 2nd (!) storey slab and thus in the average storey displacements (and so the drifts). I cannot explain it..

 

I can't see any difference for F.

 



Artur Kosakowski
Message 19 of 25
Tuctas
in reply to: Artur.Kosakowski

  It is strange, when i firstly made the investigation the results were different, now that i run again the analysis finally are the same indeed... (see the attached file that came out after the initally conversion of the table with values of stories to excel).

 

  Although, the displacements still remain different and the same thing happens to the results of modal analysis, that it is not normal.

Message 20 of 25
Artur.Kosakowski
in reply to: Tuctas

  It is strange, when i firstly made the investigation the results were different, now that i run again the analysis finally are the same indeed... (see the attached file that came out after the initally conversion of the table with values of stories to excel).

 

I'm sorry but I'm not able to investigate the situation that is impossible to be reproduced.

 

  Although, the displacements still remain different and the same thing happens to the results of modal analysis, that it is not normal.

 

I will try to check this too but it may take me some time.


 



Artur Kosakowski

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