FourNodeTetrahedron

This command is used to construct a standard four-node tetrahedron element objec with one-point Gauss integration.
element FourNodeTetrahedron $eleTag $node1 $node2 $node3
$node4 $matTag <$b1 $b2 $b3>
eleTag
|
unique element object tag |
$node1 \(node2</strong></p> <p><strong>\)node3 \(node4</strong></p></td> <td><p>four nodes defining element boundaries, input order is shown in the figure.</p></td> </tr> <tr class="odd"> <td><code class="parameter-table-variable">matTag</code></td> <td><p>tag of nDMaterial</p></td> </tr> <tr class="even"> <td><p><strong>'\)b1 $b2 $b3 |
body forces in global x,y,z directions |
Because sometimes bricks will give you headaches! Use this if you don’t care much about the stress/strain fields (tets are notoriously bad). Otherwise, you can use the 10-node quadratic tetrahedron (in development).
NOTE:
- The valid queries to a FourNodeTetrahedron element when creating an ElementRecorder object are ‘forces’, ‘stresses,’ (‘strains’ version > 2.2.0) and ‘material $matNum matArg1 matArg2 …’ Where $matNum refers to the material object at the integration point corresponding to the node numbers in the isoparametric domain.
- This element can only be defined in -ndm 3 -ndf 3
Examples
REFERENCES:
Carlos Felipa’s AFEM Course: Chapter 9 The Linear Tetrahedron.
Code Developed by José A. Abell at Universidad de los Andes, Chile