Is there any material in stko that can simulate nonlinear spring?

[2443631711@qq.com]

Dear stko team
Is there any material in stko that can simulate nonlinear spring?（Using zerolength element）
Its spring stiffness can not be a constant, but a customized curve

[STKO Team]

There are many. Try the Pinching4

[2443631711@qq.com]

Dear stko team
i have two qusetions
（1）I saw physical properties from Pysimple and Tzsimple in stko.
If I build a two-dimensional model and want to use them to simulate the zerolength connection between the liquefied soil layer (quadup element 3dofs) and the underground structure (electrical beam column element 2dof)
Can I only use the zerolengthcontactASDimplex element? Is there any other zerolength element that can be used?
（2）If the underground structure is not a pile foundation, but a tunnel or subway station, can Pysimple1 and Tzsimple1 materials be used to simulate the contact between soil and structure?

[STKO Team]

（1）I saw physical properties from Pysimple and Tzsimple in stko.
If I build a two-dimensional model and want to use them to simulate the zerolength connection between the liquefied soil layer (quadup element 3dofs) and the underground structure (electrical beam column element 2dof)
Can I only use the zerolengthcontactASDimplex element? Is there any other zerolength element that can be used?

The zeroLengthASDimplex is for contact. If you want to use those 2 uniaxial material, use them with a standard zeroLength element.

（2）If the underground structure is not a pile foundation, but a tunnel or subway station, can Pysimple1 and Tzsimple1 materials be used to simulate the contact between soil and structure?

Yes, with a standard zeroLength element as exaplained above

[2443631711@qq.com]

ummm..actully what I want to ask is whether the zeroLengthASDimplex element is the only zeroLength element used to connect 2dof and 3dof nodes

[STKO Team]

Oh yes, it's the only element that supports different DOFs at the 2 end-nodes.
With other elements, you need to duplicate nodes, and use the EqualDOF command to connect corresponding DOFs