base isolator modeling in opensees

[ams]

Hi every body
any body knows how can i model Isolator like LRB in 2D steel frame?
should i use Isolator2 spring order ?
is there any example for this purpose ? i need to model isolator in opensees but i dont have any good sources and example
PLZ help me dear teachers and students

[andreascj]

You can use elastomeric bearing element to model LRB. It's the simplest model that you should start with. Then you can also explore kikuchi bearing element and leadrubberX elements.

[ams]

This material ( kikuchi bearing element) model produces high damping rubber bearings
so if i want to model LRB i should use leadrubberX elements? i couldnt find this order for 2D model .
how can i use it for 2D model ?
and How about isolator2spring ? is it correct for modeling LRB?

[andreascj]

why don't you go with elastomeric bearing element?

[fmk]

to use a 3d element in a a 2d model mix a 2d model and a 3d model, i.e create your 2d frame as usual adding load and constraints, issue model command again and create a 3d model of the bearing, constrain the nodes of the 3d model to those of the 2dmodel using the equalDOF command and fix the out of plane nodes in 3d model.

[maksins]

Few suggestions as to when to use elastomericBearing element or LeadRubberX:
If you want to use your own material model to model a lead rubber bearing use elastomericBearing element. It will provide you flexibility to use any material model you want in axial and rotational directions, and also ability to change parameters of Bouc-Wen model in shear. It has a 2D and 3D versions.
If you want to model your lead rubber bearing using only geometric and material properties, and need to simulate additional effects under extreme loadings (e.g., heating in lead core, buckling, cavitation in tension), use LeadRubberX. It has only 3D version. But as Frank suggested, you could use a 3D elements with proper constraint with a 2D model.