3.1.10.35. ShellNL Element

This command constructs a nine-node Lagrangian shell element with membrane and drilling degrees of freedom. The command names in OpenSees are ShellNL, shellNL, ShellMITC9, or shellMITC9. Use with -ndm 3 -ndf 6.

element ShellMITC9 $eleTag $n1 $n2 $n3 $n4 $n5 $n6 $n7 $n8 $n9 $secTag

Argument	Type	Description
$eleTag	integer	unique element tag
$n1 … $n9	integer	nine nodes defining the element
$secTag	integer	tag of a previously defined section object

Note

1. This is a 3D element with 6 DOFs per node (54 total element DOFs).

2. The section is typically a PlateFiberSection or ElasticMembranePlateSection.

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

Example

1. Tcl Code

section PlateFiber 1 1 10.0
element ShellMITC9 1 1 2 3 4 5 6 7 8 9 1

2. Python Code

section('PlateFiber', 1, 1, 10.0)
element('ShellMITC9', 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 1)

Code developed by: Leopoldo Tesser, Diego A. Talledo