Joint modeling

[polatd]

Dear STKO community,

I would like to model an RC beam–column joint using a macro-model composed of a central joint shear panel, zero-length bar-slip springs, and zero-length interface shear springs, as schematically shown in the attached figure.

The beam and columns will be modeled using nonlinear force-based beam-column elements. However, I am unsure about the best way to implement the joint region and connect these three components in STKO.

https://ibb.co/1GKM3gX4

Specifically, I would like to know:

How can a joint shear panel element be modeled in STKO?
Which elements/materials should be used for the zero-length bar-slip springs?
How can interface shear springs be introduced around the joint panel?
How should the nodes and constraints be defined to obtain a stable and compatible model?

My objective is to capture the interaction between joint shear deformation, bond-slip, and interface shear behavior under cyclic loading.

I would be grateful for any modeling recommendations or examples of similar STKO/OpenSees models.

Thank you.

[STKO Team]

I would suggest you to start 1 step at a time.
Watch our webinar on the automation we have for RC beam-column joints.
Once you have it, you can use the lumped plasticity approach to include the slip section