Tube Support Element Library

This section provides a reference to the tube support elements available in Abaqus/Standard.

This page discusses:

Element Types
Nodal Coordinates Required
Element Property Definition
Element-Based Loading
Element Output
Nodes Associated with the Element

Element Types

ITSUNI: Unidirectional tube support element
ITSCYL: Cylindrical geometry tube support element

Active Degrees of Freedom

1, 2, 3, 4, 5, 6

Additional Solution Variables

None.

Nodal Coordinates Required

X, Y, Z

Element Property Definition

Input File Usage

ITS

Element-Based Loading

None.

Element Output

S11: Total direct force in the element.
S12: Tangential (shear) force component, caused by friction, in the plane of the cross-section of the tube.
S13: Tangential (shear) force component, caused by friction, parallel to the axis of the tube.

The force in the spring link and the force in the dashpot are defined as generalized substresses and, therefore, are available as substress selections in the output options, as follows:

SS1: Force in the spring link.
SS2: Force in the dashpot.

The relative axial and tangential displacements corresponding to the forces above are chosen by requesting the corresponding “strains,” except that “strain” component E13 is not defined in element type ITSCYL.

The relative tangential (shear) displacement components during slip are available as “plastic strain” components PE12 and PE13. The “equivalent plastic strain” is defined in these elements as

Δ {\bar{u}}^{s l} = \sum_{increments} \sqrt{{(Δ u_{1}^{s l})}^{2} + {(Δ u_{2}^{s l})}^{2}},

where $Δ u_{1}^{s l}$ and $Δ u_{2}^{s l}$ are the two relative tangential displacement components.

Nodes Associated with the Element

ITSUNI: Two nodes—one on the axis of the tube and one equidistant between the two parallel support plates.

ITSCYL: Two nodes—one on the axis of the tube and one at the center of the hole in the support plate.