Ls-dyna Beam elements contact

- March 8, 2024 at 5:52 am
  
  Fady Elshazly
  Subscriber
  
  Hello,
  
  1-what is the contact to tie beam to beam in Ls-Dyna. Does the contact consider the beam section or only the nodes?
  2-Also, what would be the difference in case of discrete beam.
  3- I want to use Constrained_generalized_weld_spot as unbreakable. should I defined the forces to be very high or keep them blank?. Can it be used in beam to beam and beam to shell cases?, Does the contact consider the beam and shell sections or only the nodes?
  
  thanks
- March 11, 2024 at 6:00 pm
  
  Jim Day
  Ansys Employee
  
  *CONTACT_TIED_SHELL_EDGE_TO_SURFACE will tie a beam to a shell but apparently will not tie a beam to another beam. A surface is needed on the SURFB side and beams do not have surfaces. If the model were 2D (axisymmetric or plane strain), I might work if *SET_2D_SEGMENT were used for SURFB of the contact. This approach appears not to work in a 3D model.
  *CONSTRAINED_SPOTWELD with failure values set to large, unattainable values, such as 1.e10, could be used to constrain (tie) one beam node to another beam node. In lieu of that, you could mesh the model so that the two beams share a common node.