A patch command is used to generate a number of fibers over a cross-sectional area. Currently there are three types of patches that fibers can be generated over: quadrilateral, rectangular and circular.
All patches have the following attributes:
area
Total area of the patch.
moic
Second moment of area matrix of the patch about its centroidal axis
ixc
Second moment of inertia of the patch about its \(x\) axis
iyc
Second moment of inertia of the patch about its \(y\) axis
rect(material, divs, vertices, **kwds)
matTag
Ref(Material)
tag of previously defined material (UniaxialMaterialtag for a FiberSection or NDMaterial tag for use in an NDFiberSection)
divs
[ij,jk]
ij
Int
number of subdivisions (fibers) in the IJ direction.
jk
Int
number of subdivisions (fibers) in the JK direction.
vertices
[[yI,zI],[yJ,zJ],[yK,zK],[yL,zL]]
[yI,zI]
Grp
\(y\) & \(z\)-coordinates of vertex I (local coordinate system)
yI
Num
zI
Num
[yJ,zJ]
Grp
\(y\) & \(z\)-coordinates of vertex J (local coordinate system)
yJ
Num
zJ
Num
[yK,zK]
Grp
\(y\) & \(z\)-coordinates of vertex K (local coordinate system)
yK
Num
zK
Num
[yL,zL]
Grp
\(y\) & \(z\)-coordinates of vertex L (local coordinate system)
yL
Num
zL
Num
quad(material, divs, vertices, **kwds)
matTag
Ref(Material)
tag of previously defined material (UniaxialMaterial tag for a FiberSection or NDMaterial tag for use in an NDFiberSection)
divs
[ij,jk]
ij
Int
number of subdivisions (fibers) in the IJ direction.
jk
Int
number of subdivisions (fibers) in the JK direction.
vertices
[[yI,zI],[yJ,zJ],[yK,zK],[yL,zL]]
[yI,zI]
Grp
\(y\) & \(z\)-coordinates of vertex I (local coordinate system)
yI
Num
zI
Num
[yJ,zJ]
Grp
\(y\) & \(z\)-coordinates of vertex J (local coordinate system)
yJ
Num
zJ
Num
[yK,zK]
Grp
\(y\) & \(z\)-coordinates of vertex K (local coordinate system)
yK
Num
zK
Num
[yL,zL]
Grp
\(y\) & \(z\)-coordinates of vertex L (local coordinate system)
yL
Num
zL
Num
circ(matTag, divs, center, intRad, extRad, startAng, endAng, **kwds)
matTag
Ref(Material)
tag of previously defined material (UniaxialMaterial tag for a FiberSection or NDMaterial tag for use in an NDFiberSection)
divs
[circ,rad]
circ
Int
number of subdivisions (fibers) in the circumferential direction (number of wedges)
rad
Int
number of subdivisions (fibers) in the radial direction (number of rings)
center = [0.0, 0.0]
[y,z]
\(y\) & \(z\)-coordinates of the center of the circle