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Distinguished Contributor
A.wikipedia
Posts: 140
Registered: ‎08-03-2012

Mode direction X and Y

385 Views, 13 Replies
09-15-2012 07:39 PM

Hi all.

I want find Mode direction X and Y.????

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Rafal.Gaweda
Posts: 5,604
Registered: ‎04-26-2010

Re: Mode direction X and Y

09-17-2012 12:51 AM in reply to: A.wikipedia

Look at mode shape diagrams display.



Rafal Gaweda
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Valued Contributor
Jade_Cereno
Posts: 65
Registered: ‎02-26-2013

Re: Mode direction X and Y

11-12-2013 12:25 AM in reply to: A.wikipedia

Hi,

 

My model seems to display a different mode shape than it should be

 

as my colleagues told me the mode shape is supposed to be this way:

 

mode 1 drift to x

mode 2 drift to y

mode 3 twising

 

I attach my model please take a look and help me on this

 

MIT-BsCE
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*Expert Elite* | International Moderator
Romanich
Posts: 584
Registered: ‎09-29-2009

Re: Mode direction X and Y

11-12-2013 01:10 AM in reply to: A.wikipedia
Can you upload the model? I can't see mesh on floor slabs.
   
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Valued Contributor
Jade_Cereno
Posts: 65
Registered: ‎02-26-2013

Re: Mode direction X and Y

11-12-2013 01:32 AM in reply to: Romanich

Unfortunately I cant Upload my File

 

:smileysad: its 74 mb in size

 

regarding the mesh on floor slabs, i set it to rigid diaphram and it never meshed

 

please see photo

 

MIT-BsCE
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Valued Contributor
Jade_Cereno
Posts: 65
Registered: ‎02-26-2013

Re: Mode direction X and Y

11-12-2013 01:33 AM in reply to: Jade_Cereno

by the way, the model i am using is the seismic model from robot

MIT-BsCE
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Product Support
Rafal.Gaweda
Posts: 5,604
Registered: ‎04-26-2010

Re: Mode direction X and Y

11-12-2013 01:34 AM in reply to: Jade_Cereno
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*Expert Elite* | International Moderator
Romanich
Posts: 584
Registered: ‎09-29-2009

Re: Mode direction X and Y

11-12-2013 01:47 AM in reply to: A.wikipedia
By default in this model for the floor slabs is assigned the calculation model Curtain Wall.
   
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*Expert Elite* | International Moderator
Romanich
Posts: 584
Registered: ‎09-29-2009

Re: Mode direction X and Y

11-12-2013 01:55 AM in reply to: A.wikipedia
Create new one with the same options and select Stiffening diaphragm instead of Without stiffening.
   
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Valued Contributor
Jade_Cereno
Posts: 65
Registered: ‎02-26-2013

Re: Mode direction X and Y

11-13-2013 05:34 PM in reply to: Rafal.Gaweda

hi Rafal,

 

I cant seem to open the links on what you posted. maybe our it prohibited it.

 

anyway, can i send it on your email instead?? if its possible

 

about curtain wall setting on the floor slab, I already changed it to rigid diaphram with FEM meshing.

 

still it not genereting the mode that is desirable

 

See attached three modes

 

My Colleaugues told me that member stiffening maybe the cause of mode 1 to be twisting, but I doubt that because my model is prismatic and corewalls are placed on the same place as the other, much like a mirror image.

 

Can you please help me on how to do this right?

 

From My understanding, this is the forst step to do before going to an in depth seismic analysis as I need the natural period of the building

 

 

 

 

MIT-BsCE
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