Find Attached (Tied)

Find elements that are connected to displayed elements using the Find Attached (Tied) option.

Tied elements are those that are tied to each other, but are not attached physically. This option differs from the Find Attached option, which returns elements that are physically attached to each other via common nodes.

Find Attached (Tied) is available for the LS-DYNA user profile on the QA/Model Utility menu.


Figure 1.
The relationship between tied elements is defined using the following CONTACT keywords:
Element Type Contact Keywords
ContactSpotWeld *CONTACT_SPOTWELD
NodesToSurface *CONTACT_TIED_NODES_TO_SURFACE

*CONTACT_TIEBREAK_NODES_TO_SURFACE

*CONTACT_TIED_SHELL_EDGE_TO_SURFACE

SurfaceToSurface *CONTACT_TIEBREAK_SURFACE_TO_SURFACE

*CONTACT_TIED_SURFACE_TO_SURFACE

SlidingOnly *CONTACT_SLIDING_ONLY
ConstdTieBreak *CONSTRAINED_TIE-BREAK
XtraNode *CONSTRAINED_EXTRA_NODES_NODE

*CONSTRAINED_EXTRA_NODES_SET

TiedNodes *CONSTRAINED_TIED_NODES_FAILURE
ConstRigidRbody *CONSTRAINED_RIGID_BODIES

Features

  • Find Attached (Tied) returns any tied elements connected via TIED_CONTACTS as defined using LS-DYNA.
  • You can perform a Find Attached (Tied) operation on one or more displayed elements or components.
  • Element input and output is based on dimension as follows:
  • Input (displayed) Output (attached or tied)
    1D/3D elements 2D elements
    2D elements 1D/3D elements
    2D elements 2D elements
    Note: For ContactSpotweld, the 1st and 2nd use case is valid.

Use Cases

Use Case 1:
Two independent beam nodes are connected to a common layer.
Result:
If you start with the green shell and 1D beam in image 1., then the Find Attached (Tied) operation returns the elements in the following sequence:


Figure 2.


Figure 3.


Figure 4.


Figure 5.
Use Case 2:
A common node between two 1D elements.
Result:
If you start with the 1D beam in image 1., then the Find Attached (Tied) operation returns the elements in the following sequence:


Figure 6.


Figure 7.


Figure 8.
Note: The Find Attached (Tied) option works with displayed elements only.