non-linear Zerolengthcontact3d !?

[speranza]

My dear friends.
How can we define an upper bound for shear strength in a zerolengthcontact3D element?
The zerolengthcontact3D is a node to node connection element which has a linear behavior. I wonder
if I could define an upper bound for this element to use it in a non-linear model or any alternative !?

In ANSYS we have contact 52 .

[vesna]

This element does not have an option of defining the upper bound. An alternative would be to add a spring (zeroLenght element) between the same nodes and to assign appropriate uniaxial materials to it that would by acting in parallel with zerolengthcontact3D element establish the upper bound.

[speranza]

thank you vesna, but I think In a parallel model, strains are equal and stresses and stiffnesses are
additive so as there is not any upper bound for Zerolengthcontact3d, there is not any upper bound for parallel model. I think the series model can be a solution because stresses are equal and strains and flexibilities are additive.

[vesna]

If you want to bound the force, you can still use two elements in parallel. If to Zerolengthcontact3d element, whose strength is linearly increasing, you add another element whose strength after reaching certain deformation starts decreasing you can create the upper bound.

[speranza]

Yes of course, That's right. Thank you vesna.