Beam contac

[HumbertHumbert7]

Is this problem implemented?
How can I solve it?
Thank you

[permas4edu]

I guess you ask for a static contact analysis. This problem can be solved in PERMAS. Can you provide the geometrical (i.e. cross-section, length) and material properties (Young's modulus) of the elastic beam? Is it a distributed load? How large is the load?

[tsarikahin]

@HumbertHumbert7 Sorry for the late answer.

This problem is not implemented. But by applying Karush-Kuhn-Tucker inequalities, this can be solved. However, KKT constraints are formulated only for 2D domains. You need to modify them based on the 1D beam example.

Steps:

• You must define a possible contact area search (possibly the whole domain)
• generate, KKT constraints (gap has to be positive, normal pressure has to be negative and multiplication has to be zero)

To enforce KKT constraints, you can use the Fisher-Burmeister function, but still, you have to calculate the gap and normal pressure (Normal pressure would be in this case the pressure in vertical direction, so the shear stress)

Thats basically all.

[HumbertHumbert7]

Hi, thank you very much for your responses. it doesn't matter if the problem is not implemented, I have considered some other contact mechanics problem for which I have proceeded as indicated by tsarikahin and I have founded very useful the paper you have published.

[tsarikahin]

@HumbertHumbert7 Thank you for your kind words. Please feel free to make a PR to add your examples.

[permas4edu]

[permas4edu]

The clamped-clamped beam is loaded by a line load. A node to ground contact with an initial gap is used here. Moreover, a hard contact is used in PERMAS.