joint2D element ; panel zone, rotation of beam ends

[seyedalirezajalali]

the joint2D element is a useful element for modeling the panel zone as well as the rotational deformability of beam ends. as this element is not described in documentation neither in pdf nor in HTML format , I thought it would be helpful for other users to put the parameters of this command:

element Joint2D tag? Nd1? Nd2? Nd3? Nd4? NdC? [Mat1? Mat2? Mat3? Mat4?] MatC? LrgDspTag?

tag: unique element tag
Nd1: integer tag indicating node 1
NdC: integer tag indicating the central node. this tag is used for generating the internal node (the node is generated automatically by element command) and must not exist in the domain
Mat1 ~ Mat4 :a group of optional integer tags indicating the uniaxial materials for interface rotational springs injoint2D model. use a zero tag to indicate the case that a beam-column element is rigidly framed to the joint
MatC : uniaxial material for the shear panel behavior
LrgDsdTag: 0 for small deformations and constant geometry; 1 for large deformations and time varying geometry; 2 for large deformations ,time varying geometry and length correction

the nodes must be located such that the main chords bisect, and the node tags are required to be entered in a clockwise or counter-clockwise order

source:"simulation and damage models for performance assessment of reinforced concrete beam-column joints" by Arash Altoontash

[seyedalirezajalali]

the link for mentioned source is here:
opensees.berkeley.edu /OpenSees/doc/ Altoontash_Dissertation.pdf

[talebian.s.e]

hi,
i have a problem about element joint2d.
when i use it opensees says "invalid command element."
would u please help me to know how i can use it?

thanks for your attention.

[seyedalirezajalali]

Hi.
Could you post your script to see what the problem exactly is?

[talebian.s.e]

thanks

[seyedalirezajalali]

hi.
the problem is clear. Joint2d nodes must represent nodes at four edges of panel zone, they shall not fall on each other. you must use the dimensions of your panel zone.
--------*3

4*-------------*2

--------*1

[talebian.s.e]

hi,
Thank you very much.
I will try it and notify you the result.

[talebian.s.e]

hi,
Thanks for your help.
I dont know about the recorders of element joint2D . specialy displacement of central node.
would you tell me the command?

[talebian.s.e]

Dear seyedalirezajalali

How can I use two rotational spring in element joint2D?
Would you please help me?

actually I should dedicate two response to the joint.


thanks a lot.

[modir24]

Hi Alireza jan

I always get errors regarding the MP constraint in the joints. I don know how to tackle that. equalDOF is the proper command for that; but i don't know "where" to use it. because as I know, I have to constrain the 4 nodes around the joint to the center node but the center node is defined where we define the joint2D therefore equalDOF cannot be defined before it.
do you have any idea?

[fmk]

that error will go away in the next release.

[talebian.s.e]

thanks

[modir24]

the above mentioned errors have caused my model from being built properly because the eigen analysis cannot be performed. the only problem I have are the Joint2D s. do you have any idea how joint problem can be solved?

I have defined 4 nodes around the joint. in the Joint2D definition I give each node an Ibarra material.
my work is stopped only for this command and I don have a bit of a clue what I can do

[fmk]

the problem is that the joint2d command also creates a MP_Constraint. the tag for the constraint is hidden from the user; if other constraints are present there is a conflict with the tags beacuse of the #'s the joint command uses.

[modir24]

I have not defined any constraints for any of the nodes around joints