Generalized beam theory applied to shear stiffness

There is no consensus of opinion on the correct expressions for shear stiffness, even in the apparently simple case of rectangular sections made from homogeneous isotropic material. A general beam theory has been proposed which is applicable to all regular prismatic systems. This has been used to find the appropriate beam-like flexibilities for trusses. The same approach can be used for normal beams, giving values for the shear stiffnesses of various cross-sections as particular results of a general theory embracing torsion, binding, extension and shear of regular prismatic systems.