Torsion

The twist or deformation of a body set up by a torque.

Torsion Theories

 * Saint Venant torsion theory - basic torsion theory for which warping is not restrained
 * Vlasov torsion theory - more general torsion theory for which warping can be restrained

Notation
The following notation is used throughout the torsion topic, unless noted otherwise:


 * B ... bimoment
 * I_{\omega} ... sectorial moment of inertia
 * \phi ... angle of rotation due to torsional moment
 * \phi' ... first derivative of \phi with respect to the local X axis of the member
 * \phi'' ... second derivative of \phi with respect to the local X axis of the member
 * \phi''' ... third derivative of \phi with respect to the local X axis of the member