Axial–torsional coupled static behavior of inhomogeneous pretwisted cantilever beams

This study investigates the axial–torsional coupled static behavior of inhomogeneous pretwisted cantilever beams. The problem is formulated using the Saint–Venant torsion assumption, and warping-related stiffness coefficients are reexpressed in terms of Prandtl’s stress function. It is assumed that material distribution is parabolic in the thickness direction. Governing equations are derived using the minimum potential energy approach. To verify the approach used to compute warping-related stiffness coefficients in the inhomogeneous case, several validation studies are performed by comparing results with those obtained from the finite element analyses and multi-material beam approach. The effect of the material distribution parameter on these coefficients is examined. Then, for tip tensile force and tip torsional moment scenarios, it is shown that computed structural responses are in good agreement with those obtained from commercial finite element software. Finally, the effect of the material distribution parameter on the tip displacements is analyzed for these two loading scenarios. It is shown that in addition to geometric parameters, inhomogeneity can also affect the axial–torsional coupled static response of the pretwisted beam.