Contents  
Functions  
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Purpose
4 and 8 node quadrilateral plate/shell elements.
Description
In a model description matrix, element property rows for quad4, quadb and mitc4 elements follow the standard format
[n1 ... ni MatID ProID EltID Theta Zoff T1 ... Ti]
giving the node identification numbers ni (1 to 4 or 8), material MatID, property ProID. Other optional information is EltID the element identifier, Theta the angle between material x axis and element x axis, Zoff the off-set along the element z axis from the surface of the nodes to the reference plane (use feutil Orient command to check z-axis orientation), Ti the thickness at nodes (used instead of il entry, currently the mean of the Ti is used).
If n3 and n4 are equal, the tria3 element is automatically used in place of the quad4.
Isotropic materials are currently the only supported (this may change soon). Their declaration follows the format described in m_elastic. Element property declarations follow the format described p_shell.
Supported formulations (f value stored in il(3) p_shell entries for isotropic materials and element default for composites) are
The definition of local coordinate systems for composite fiber orientation still needs better documentation. Currently, q4cs the only element that supports composites, uses the local coordinate system resulting from the BuildNDN 23 rule. A temporary solution for uniform orientation is provided with model=feutilb('shellmap -orient dx dy dz',model).
Supported formulations (p_shellil(3) for isotropic materials and element default for composites) are
See also
m_elastic, p_shell, fe_mk, feplot