EPP only compression material with different behavior for positive and negative displacement

[xantis85]

Hello to everyone,
I'm trying to model an Elastic-Perfectly Plastic behavior adopting EPP material, but I need to have only-compression behavior. In particular, with two branches for positive displacements and two for negative displacements (please see the attached figure in the dropbox link). I'm trying to compose the behavior using parallel material but it seems to be too much complicated.

https://www.dropbox.com/s/mr0m785v3e6pa ... 5.png?dl=0

There is any option in OpenSees to easy model this behavior?

Thanks in advance

xantis85

[selimgunay]

Did you try the elastic-perfectly plastic gap material?

https://opensees.berkeley.edu/wiki/inde ... p_Material