# Torsion Constant
In structural elements capable of sustaining torsional moments it is necessary to define a constant to specify the ‘twisting stiffness’.
This term is referred to as the Torsion Constant. The following notes offer guidance on how to calculate the Torsion Constant. More detailed information may be found in the standard texts.
In the literature there is some confusion over the symbol used to
represent the Torsion Constant. In many texts it is referred to as
If a circular bar of constant cross section and of length
When the cross section of the bar is non-circular, plane cross sections
do not remain plane after deformation and warping will occur.
Nevertheless the above equation can still be used with good accuracy,
but I should be taken as the appropriate Torsion Constant