MixedBrick

This command is used to construct an eight-node mixed volume/pressure brick element object, which uses a trilinear isoparametric formulation.

Command

element bbarBrick $tag $node1 $node2 $node3 $node4 $node5 $node6 $node7 $node8 $matTag <$b1 $b2 $b3>

Argument	Type	Description
$tag	integer	unique element object tag
$node1 .. $node8	8 integer	nodes of brick (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

Fig. 34 BbarBrick element node numbering

Note

The valid queries to a Brick 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 with -ndm 3 -ndf 3

Example

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

1. Tcl Code

   element bbarBrick 1 1 2 3 4 5 6 7 8 1 $b1 $b2 $b3
   

2. Python Code

   model.element('bbarBrick',1, (1,2,3,4,5,6,7,8), 1, (b1, b2, b3))
   

Code Developed by: Edward Love, Sandia National Laboratories