# 3.1.9.20. TenNodeTetrahedron Element¶

This command is used to construct an ten-node tetrahedron element object, which uses the standard isoparametric formulation.

Command

element TenNodeTetrahedron \$eleTag \$node1 \$node2 \$node3 \$node4 \$node5 \$node6 \$node7 \$node8 \$node9 \$node10 \$matTag <\$b1 \$b2 \$b3>

Argument

Type

Description

\$eleTag

integer

unique element object tag

\$node1 .. \$node10

10 integer

nodes of tet (ordered as shown in fig below)

\$matTag

integer

tag of nDMaterial

\$b1 \$b2 \$b3

list float

optional: body forces in global x y z directions

This element is based on second-order interpolation of nodal quantities, this means that the strain and stress field inside the element are linearly interpolated. Four Gauss-points inside the element are used for integration.

Fig. 3.1.9.22 TenNodeTetrahedron Element Node Numbering

Note

The valid queries to a TenNodeTetrahedron 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 after a model Command with -ndm 3 -ndf 3

Example

The following example constructs a TenNodeTetrahedron element with tag 1 between nodes 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 with an nDMaterial of tag 1 and body forces given by varaiables b1, b2, b3.

1. Tcl Code

```element TenNodeTetrahedron 1 1 2 3 4 5 6 7 8 9 10 1 \$b1 \$b2 \$b3
```
1. Python Code

```element('TenNodeTetrahedron',1, 1,2,3,4,5,6,7,8,9,10, 1, b1, b2, b3)
```

Code Developed by: José Antonio Abell and José Luis Larenas (UANDES). For bugs and features, start a new issue on the OpenSees github repo and tag me (@jaabell).