Flatsliderbearing for 2d 2dof model
Moderators: silvia, selimgunay, Moderators
Flatsliderbearing for 2d 2dof model
Hi,
Could you please help on what is the possible way to include base isolator (for example, flatsliderbearing) into a 2d 2dof model?
Thanks,
C.
Could you please help on what is the possible way to include base isolator (for example, flatsliderbearing) into a 2d 2dof model?
Thanks,
C.
Re: Flatsliderbearing for 2d 2dof model
Zerolength element ?
Re: Flatsliderbearing for 2d 2dof model
I know I can use zerolength element or twonode link element with a finite length. However, the problem is while all the nodes in my model are 2dof, the nodes that I connect a flatslidebearing element require to have 3dof. Therefore, my question to you is that have you ever utilized flatsliderbearing element in a 2d 2dof model before?
Thanks.
Thanks.

 Posts: 850
 Joined: Mon Sep 09, 2013 8:50 pm
 Location: University of California, Berkeley
Re: Flatsliderbearing for 2d 2dof model
You can use it for a 2D problem, please see the descriptions and examples in the below link
http://opensees.berkeley.edu/wiki/index ... ng_Element
http://opensees.berkeley.edu/wiki/index ... ng_Element
Re: Flatsliderbearing for 2d 2dof model
Selim hocam merhabalar,
My models consist of 4 node quad elements with 2 dof per node. However, the flatslidebearing element requires the nodes to have 3 dof. That is why it creates a problem when i try to place the bearing in my model. To connect two different models (for example 2d 2dof and 2d 3dof) I employed equal degree of freedom multipoint constraints. I believe it works in the same way, but is there an other way that this bearing element works also in a 2d 2dof model?
Thanks in advance,
Cagatay
My models consist of 4 node quad elements with 2 dof per node. However, the flatslidebearing element requires the nodes to have 3 dof. That is why it creates a problem when i try to place the bearing in my model. To connect two different models (for example 2d 2dof and 2d 3dof) I employed equal degree of freedom multipoint constraints. I believe it works in the same way, but is there an other way that this bearing element works also in a 2d 2dof model?
Thanks in advance,
Cagatay

 Posts: 850
 Joined: Mon Sep 09, 2013 8:50 pm
 Location: University of California, Berkeley
Re: Flatsliderbearing for 2d 2dof model
Cagatay merhaba,
I think you can fix the rotational DOF. It seems this is what is done in the examples in the wiki page.
http://opensees.berkeley.edu/wiki/index ... er2d_2.tcl
I think you can fix the rotational DOF. It seems this is what is done in the examples in the wiki page.
http://opensees.berkeley.edu/wiki/index ... er2d_2.tcl
Re: Flatsliderbearing for 2d 2dof model
Selim hocam merhabalar,
I modelled the bearing element in the way I explained above and it gives a warning such:
WARNING FlatSliderSimple2d::setUp()  element: 300  ignoring nodes and using specified local x vector to determine orientation.
WARNING FlatSliderSimple2d::setUp()  element: 301  ignoring nodes and using specified local x vector to determine orientation.
WARNING FlatSliderSimple2d::setUp()  element: 302  ignoring nodes and using specified local x vector to determine orientation.
WARNING FlatSliderSimple2d::setUp()  element: 303  ignoring nodes and using specified local x vector to determine orientation.
And it gives a structural period of 7.86 seconds for the first 5 periods same. The fundamental period of the building was 0.29 s without the slide bearing element. Do you think this is okay? Or too much difference which happens because of a wrong assumption in the model?
Thanks,
Cagatay
I modelled the bearing element in the way I explained above and it gives a warning such:
WARNING FlatSliderSimple2d::setUp()  element: 300  ignoring nodes and using specified local x vector to determine orientation.
WARNING FlatSliderSimple2d::setUp()  element: 301  ignoring nodes and using specified local x vector to determine orientation.
WARNING FlatSliderSimple2d::setUp()  element: 302  ignoring nodes and using specified local x vector to determine orientation.
WARNING FlatSliderSimple2d::setUp()  element: 303  ignoring nodes and using specified local x vector to determine orientation.
And it gives a structural period of 7.86 seconds for the first 5 periods same. The fundamental period of the building was 0.29 s without the slide bearing element. Do you think this is okay? Or too much difference which happens because of a wrong assumption in the model?
Thanks,
Cagatay