Define the plastic torsional moment behavior for frame elements.
This option can be used only in conjunction with the FRAME SECTION option and is available only for FRAME3D elements. It describes the torsional moment in a frame element as a function of the plastic rotation about the element's axis.
There are no parameters associated with this option.
Data lines to define the variation of torsional yield moment with plastic rotation
First line
Torsional yield moment, .
Plastic rotation about the element's axis.
Repeat this data line as often as necessary to define the relationship between the torsional moment and the plastic rotation. At least three pairs of data are required.