Skip to content

Element Commands

Element commands define elements, elsets, and element properties.

  • *ELEMENT: Define elements.
  • *ELSET: Define elsets.
  • *ELGEN: Generate elements.
  • *ELCOPY: Copy elements.
  • *Section: Define element properties for elsets.

Elements are assigned a unique integer ID greater than 1 (element ID) for later use. An elset is a collection of elements that are assigned a unique name as a string.

The number of nodes connected to an element depends on the element type. Element properties include section properties that can be shared by multiple elements or specific properties applied to individual elements. Special elements, like Cable or EmbeddedLine elements, may have field values that change depending on the analysis step. The field values output as results are predefined depending on the element type. These values can be defined at element nodes, Gauss points, or the element center. More details can be found in "Chapter 4: Element Library."

Section properties common to element types or individual properties for elements can be defined using the *Element command, but you can also define node connectivity first and assign properties later using the *Distribution command.

*Element

Define elements.

*Element, Type=type [, ELSet=elset, Offset=nodeIdOffset, elementIdOffset]
 id, n1, n2, ...[, S=section], [...]
 ...
Keyword line
  • Type=type: Specifies the element type (required). The element type is predefined, such as Truss or Hexa8.
  • ELSET=elset: Specify the elset to which the defined elements will belong. If no predefined elset exists, a new one is created (optional).
  • Offset=nodeIdOffset, elementIdOffset: Offset for node and element IDs (optional; default: 0,0).
First data line and subsequent data lines
  • id, n1, n2, ...: Specifies the element ID and connected nodes (n1, n2, ...). The number of connected nodes depends on the element type.
  • S=section: Section properties that can be applied to multiple elements depending on the element type. These can also be assigned later with the *Distribution, TYPE=Section command.
  • ...: Specific element properties depending on the element type. For example, a beam element’s local coordinate system can be specified as CS=cs. These can also be assigned later with the *Distribution command.

*Section

Define element properties.

*Section, Type=type, Name=name
 ...
Keyword line
  • TYPE=section_type: Specifies the section type, such as Truss, Cable, or Solid.
  • Name=name: Specifies the section name.

More details on section types can be found in "Chapter 4: Element Library."

*ELSET

Define an elset.

*ELSet, Type=Select|Surface|Box, Name=elset
  source, ... ,
  ...
Keyword line
  • TYPE={Select|Surface|Box}: Specifies how to assign elements to the set. If omitted, the default: SELECT.
    • Select: Assign elements manually.
    • Surface: Assign elements that form a surface.
    • Box: Assign elements that meet the criteria of a specified range.
  • Name=elset: The name of the elset (required). If no predefined elset exists, a new one is created.

The *ELSET command adds predefined elements to a new or existing elset.

If there is no data line and the elset already exists, no action is taken. Otherwise, an empty elset is defined.

*ELSET, TYPE=Select

Assign element IDs, elsets, or element number patterns to a specified elset or remove elements from it.

*ELSet, Type=Select, Name=elset
  source, ...
  ...
First data line and subsequent data lines
  • source: Element IDs, elsets, or element number patterns to be added to the elset. Patterns use the format start:end:spacing, with spacing omitted if it is 1. Prefix with - to remove elements from the set.

If the source is an elset, all elements in that set are added to the specified elset.

Example
*ELSET, Name=C
 10, 19, 15, 20:24:2

*ELSet, Type=Select, Name=A
 1, 10, left  # Elements 1, 10, and all elements in the "left" set are assigned to "A".

*ElSet, Type=Select, Name=B
 A, -2, B, -C  # Remove element 2 from set A, add elements from set B, and remove elements from set C.
 -1:5:2, 9:11  # Supports removal operations in element number patterns as well.

*ElSet, Type=Surface

Assign elements that form a surface to an elset.

*ElSet, Type=Surface, Name=name
  target, ...
  ...
First data line and subsequent data lines
  • target: Name of the surface.

The command assigns the elements that form the surface specified in the data line to the elset. If the elset already exists, elements are added to it.

Example
*ElSet, Type=Surface, Name=Connected
 upstream, bottom

*ElSet, Type=Box

Assign elements to a set if all their nodes are within the boundaries xmin < X < xmax, ymin < Y < ymax, zmin < Z < zmax.

*ELSet, Type=Box, Name=name
  [X=xmin,xmax] [Y=ymin,ymax] [Z=zmin,zmax] [ELSET=target]
  ...
First data line and subsequent data lines
  • X=xmin,xmax: X-direction boundaries for the box [L].
  • Y=ymin,ymax: Y-direction boundaries for the box [L].
  • Z=zmin,zmax: Z-direction boundaries for the box [L].
  • ELSET=target: Specify the elset to search within (optional). If not provided, the entire model is searched.
Example
*ELSet, Type=Box, Name=BoxSet
 X=0.1, 100, Y=10., 20.

*ELSet, Type=Box, Name=leftSlab
 X=0.1, 100, ELSet=Slab

*ELSet, Name=rightOnSlab
 Slab, -leftSlab

*ELGEN

Generate elements.

*ELGEN, ELSET=elset
  masterElement, iNEL, iNodeInc, iELInc, jNEl, jNodeInc, jELInc, kNEL, kNodeInc, kELInc
  ...
Keyword line
  • ELSET=elset: Specify the elset to which the generated elements will belong (optional).
First data line and subsequent data lines
  • masterElement: Predefined master element ID (required).
  • iNEL, iNodeInc, kELInc: Generate iNEL elements in the i-direction (first direction). Element numbers increment by iELInc, and connected node numbers increment by iNodeInc (optional; default: 1,1,1).
  • jNEL, jNodeInc, jELInc: Generate elements in the j-direction (second direction) in the same manner as the i-direction (optional; default: 1,1,1).
  • kNEL, kNodeInc, kELInc: Generate elements in the k-direction (third direction) in the same manner as the i-direction (optional; default: 1,1,1).

Generated elements only include node connectivity. Section properties and individual element properties are not copied and must be assigned separately using the *Distribution, TYPE=Section command.

Example
*Element, Type=B3D2H
 100, 1, 2
*ELGen ELSet=rail
 100, 10, 100, 10
*Distribution, TYPE=Section
 rail, rail

*ELCOPY

Copy elements.

*ELCopy, ELSet=elset[, Multiple=multiple]
  source_elset, elmInc, nodeInc
  ...
Keyword line
  • ELSET=elset: Optional elset for the newly created elements. The elements in source_elset are not included. If no elset exists, a new one is created.
  • MULTIPLE=multiple: Number of times to repeat the ELCOPY operation (optional; default: 1).
First data line and subsequent data lines
  • source_elset: Elset to be copied (required).
  • elmInc, nodeInc: Increment values for element and node IDs (required). Connected nodes must be predefined.

Generated elements only include node connectivity. Section properties and individual element properties are not copied and must be assigned separately using the *Distribution, TYPE=Section command.

Example
*ELCopy, ELSet=diaphram
 diaphram0, 2000, 2000