Robot Structural Analysis Forum
Welcome to Autodesk’s Robot Structural Analysis Forums. Share your knowledge, ask questions, and explore popular Robot Structural Analysis topics.
cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 

Mode Shape X & Y components of Center of Diaphragm

18 REPLIES 18
SOLVED
Reply
Message 1 of 19
djan0521
3359 Views, 18 Replies

Mode Shape X & Y components of Center of Diaphragm

Hi,

 

I'm using Robot for a 63 story building. My Boss ask me to generate the X and Y components of the Mode Shape displacement (unitless) for every floor similar to the attached table from ETABS. Can we do it in Robot? This data wil be used for wind tunnel test. Thanks

 

Kind Regards,

Jan

Tags (2)
18 REPLIES 18
Message 2 of 19
Rafal.Gaweda
in reply to: djan0521

Not for a floor = center of diaphragm; for real nodes only , you an get them in Modal Analysis Results table



Rafal Gaweda
Message 3 of 19
djan0521
in reply to: djan0521

Thanks, I found it.

Message 4 of 19
trandtrung00
in reply to: djan0521

Hi Dian021 ,I had the same problem but i could not find the result as you found.Can you show me where is it in the Robot program or just post some picture of it.

Thank regard !!

This is the result i hae in Etabs but I can't find it In Robot .Please help !

Etab Building Modal.png

Message 5 of 19
mpcloob
in reply to: Rafal.Gaweda

in the name of GOD .
hello rafal
please attach a picture for this your answer....thanks
Message 6 of 19
Rafal.Gaweda
in reply to: mpcloob

eigenv.jpg



Rafal Gaweda
Message 7 of 19
Tuctas
in reply to: djan0521

 The displacement values of any node of the structure corresponding to a given eigenshape can be viewed when choosing the option “Deformations” in the “Diagrams for buildings” (see attached). They should also be displayed in a table form.

 

  Keep in mind that the values that are viewed with the above option are the total ones (i.e the square root of the sum of squares of each component) and that they are not normalized to 1.

Message 8 of 19
trandtrung00
in reply to: Tuctas

Thank Rafal ,Tuctas for  answer 

I am sorry for my question but when i try to follow your post it does not happen as you said .I use RSAP 2011.And the value of Eigenvector in modal analysis table are all node of modal,it hard for me to find the value i need as Etab.Sorry for my English

Many thanks!

my modal 

 

1.png

Message 9 of 19
trandtrung00
in reply to: trandtrung00

Message 10 of 19
Rafal.Gaweda
in reply to: trandtrung00

Every node belonging to each diaphragm in your model will have the same UX UY so take any of them: http://screencast.com/t/47Nmw6Ti



Rafal Gaweda
Message 11 of 19
trandtrung00
in reply to: djan0521

I really apreciate your help.Thank you very much !!!

Message 12 of 19
Tuctas
in reply to: trandtrung00

  That similarity of the values between any node of each diaphragm was "by accident" because of the total symmetry of the model. Obviously, this is not the case in general.

  It seems that in the program the "deformation" values that are displayed for the center of diaphragm corresponding to each mode appears occasionally (maybe they don't appear when there are too many nodes, like it is for F.E of panels). 

  It would be useful if that information of displacements of eigenvalues for the center of diaphragm was displayed in a table form together with the other nodes of the structure.    

Message 13 of 19
trandtrung00
in reply to: Tuctas

"It would be useful if that information of displacements of eigenvalues for the center of diaphragm was displayed in a table form together with the other nodes of the structure"

yes i think so,.thank Tuctas for your explain !

Message 14 of 19
Jade_Cereno
in reply to: djan0521

Hi,

 

I would like to know what causes my mode shape to be not the same as etabs?

 

mode 1 supposed to be drifting x

mode 2 supposed to be drifting y

mode 3 supposed to be twisting

 

also, i would like to know how to get the natural period of a structure using robot

 

I attach my file here

 

thanks!!

MIT-BsCE
Tags (1)
Message 15 of 19

Hello everyone,

How can i see the mode shapes of the structure in a modal analysis. I want to see it on the actual model not just numbers in a table. does robot have this feature?
Message 16 of 19
Message 17 of 19
huythangdhbk91
in reply to: djan0521

hi Rafal,

I have the same questions with djan0521. for snip 2 code. I must use drift ratio ( of each story and each mode). The dyamic wind is caculated based on it.

how export this value.

please help us, thanks you

Message 18 of 19

I told you yesterday - there are no such results for Modal case in Robot.


Rafal Gaweda
Message 19 of 19

Thanks Rafal.

I hope them will active soon.

🙂

Can't find what you're looking for? Ask the community or share your knowledge.

Post to forums  

Autodesk Design & Make Report