This command is used to construct the Corotational Coordinate Transformation (CorotCrdTransf) object. Corotational transformation can be used in large displacement-small strain problems. NOTE: Currently the transformation does not deal with element loads and will ignore any that are applied to the element.
For a two-dimensional problem:
|geomTransf Corotational $transfTag <-jntOffset $dXi $dYi $dXj $dYj>|
For a three-dimensional problem:
|geomTransf Corotational $transfTag $vecxzX $vecxzY $vecxzZ|
|$transfTag||integer tag identifying transformation|
|$vecxzX $vecxzY $vecxzZ||X, Y, and Z components of vecxz, the vector used to define the local x-z plane of the local-coordinate system. The local y-axis is defined by taking the cross product of the vecxz vector and the x-axis.
These components are specified in the global-coordinate system X,Y,Z and define a vector that is in a plane parallel to the x-z plane of the local-coordinate system.
These items need to be specified for the three-dimensional problem.
|$dXi $dYi||joint offset values -- absolute offsets specified with respect to the global coordinate system for element-end node i (optional)|
|$dXj $dYj||joint offset values -- absolute offsets specified with respect to the global coordinate system for element-end node j (optional)|
The element coordinate system is specified as follows:
The x-axis is the axis connecting the two element nodes; the y- and z-axes are then defined using a vector that lies on a plane parallel to the local x-z plane -- vecxz. The local y-axis is defined by taking the cross product of the vecxz vector and the x-axis. The z-axis by taking cross product of x and new y. The section is attached to the element such that the y-z coordinate system used to specify the section corresponds to the y-z axes of the element.
- Element 1 : tag 1 : vecxZ = zaxis
geomTransf Corotational 1 0 0 -1
- Element 2 : tag 2 : vecxZ = y axis
geomTransf Corotational 2 0 1 0
Code Developed by: Remo Magalhaes de Souza
Images Developed by: Silvia Mazzoni