Finite element vibration analysis of rotating Timoshenko beams

The stiffness and mass matrices of a rotating twisted and tapered beam element are derived. The angle of twist, breadth and depth are assumed to vary linearly along the length of beam. The effects of shear deformation and rotary inertia are also considered in deriving the elemental matrices. The first four natural frequencies and mode shapes in bending-bending mode are calculated for cantilever beams. The effects of twist, offset, speed of rotation and variation of depth and breadth taper ratios are studied. (C) 2001 Academic Press.