Find Attached (Tied)

Find Attached (Tied) is an option that you can use to find elements that are connected to displayed elements. 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.

Location

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

Find_attached_tied2

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

Following are two use cases for Find Attached (Tied):

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:
	1.
	2.
	3.
	4.

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:
	1.
	2.
	3.

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