3.1.10.36. Bbar Plane Strain Quadrilateral Element

This command constructs a four-node quadrilateral element using a bilinear isoparametric formulation with a mixed constant pressure/volume (B-bar) assumption. The command names in OpenSees are bbarQuad or mixedQuad. The element is for plane strain problems only. Use with -ndm 2 -ndf 2.

element bbarQuad $eleTag $iNode $jNode $kNode $lNode $thick $matTag

Argument	Type	Description
$eleTag	integer	unique element tag
$iNode $jNode $kNode $lNode	integer	four nodes in counter-clockwise order
$thick	float	element thickness
$matTag	integer	tag of an nD material

Note

1. Plane strain only; not valid for plane stress problems.

2. Valid Element Recorder queries include forces, stresses, and material $matNum ....

Example

1. Tcl Code

element bbarQuad 1 1 2 3 4 1.0 1

2. Python Code

element('bbarQuad', 1, 1, 2, 3, 4, 1.0, 1)

Code developed by: Ed Love