Contact forces in compression test

[dxvn818]

Hello all,

I am doing simulation for compression test of a steel tube. As I understand, a continuum solid domain is discretised into discrete elements. Discrete elements are linked by cohesive beam or spring and  their interaction are calculated based on the reaction forces and torques of the beam bond. In the compression test, the discrete elements may overlap each other and when damage occurs, some beam bond may break.

1. In case that some beam bonds linked between discrete elements are broken, those discrete elements move closely to each other and collide, then how is the interaction force between two discrete elements without any bond calculated ?

2. In case that discrete elements overlap each other due to compression force, is the interaction force still calculated by beam reaction only or with the addition force from interpenetration distance (as in plug in "_ManageCollision") ?

Best Regards,
Vinh

[Damien André]

Hello,

dxvn818 wrote

1. In case that some beam bonds linked between discrete elements are broken, those discrete elements move closely to each other and collide, then how is the interaction force between two discrete elements without any bond calculated ?

If you don't use the _ManageCollision plugin, the contact force are not computed. So, nothing happens

dxvn818 wrote

2. In case that discrete elements overlap each other due to compression force, is the interaction force still calculated by beam reaction only or with the addition force from interpenetration distance (as in plug in "_ManageCollision") ?

If you have beams AND   "_ManageCollision" plugin, both forces (from bond and contact) are calculated. But, you can use a trick here. If you put the "ExcludeBondedDiscreteElements=True" option into the "_ManageCollision" plugin, the contacts are ignored if the discrete elements are bonded by a beam. If not, the contact is computed.

kind regards, Damien.

[dxvn818]

Hi Damien,

Thank you. I will make some other tests.

Kind Regards,
Vinh