Abaqus - Contact with friction behaviour

[SofiaB]

Hello,

I am modeling a truss subjected to a vertical displacement(load) in the tip. The problem I'm having is, after a experimental analyses I observed buckling in the chord and a contact between the truss chord and a restraining lateral device That incread the rigidity of the truss( the truss can freely move in vertical direction but in the horizontal it can move only the small gap between truss and constraining device)


In abaqus I used several connectors to represent a non linear spring to try and have the same rigid increace as the real model, but can't seem to achieve that(I used a constrain to associate the center of the chord to it's edges and then in the center aplied the conectors)

In advancing the approach involving contact I thought about adding a friction behavior on the connectors but now I have a problem in defining the coontact force. Does anyone know how i should calculate the internal contact force? Should I specify the component?

Thanks in advance for all the much needed help.

Note: for the buckling representation I have used a horizontal displacement and the geometric nonlinearity it's already on.
for the friction tangential behavior I used: Penalty and the only parameter i defined was a friction coeff of 0.4

 

[FEA way]

To specify internal contact force add Friction behavior and choose User-defined, Contact Force as Friction model. You can find more details in the documentation chapter "Connector friction behavior" (paragraph "Specifying the internal contact force").

 

[SofiaB]

Thank you very much! One more thing, since I am introducing contact friction I have to add new field and history output.
Does this choice seem good so that I don't have the message "The selected Primary Variable is not available in the current frame for any elements in the current display group"?
- Field output: CForce, Cstress
- History output: CSF3, CNF3
being the 3 direction the one corresponding to the axial direction of the conectors.

 

[FEA way]

These variables are used with contact interactions. Connectors have their own specialized output. You can find a full list of these variables in "Connector element library" chapter of the documentation.