A mixed-hybrid finite element for three-dimensional isotropic helical beam analysis

This paper presents a two node finite element with six degrees of freedom per node, able to model the behaviour of a three-dimensional isotropic helical beam with two constant radii of curvature (curvature and torsion radii). The formulation, which includes the shear strain effects, is based on the assumed resultant forces hybrid approach. The resulting forces approximation verifies exactly the equilibrium equations. Numerical results of samples and distribution of generalized forces along the helical beam are presented. Comparison with other models indicates that the presented element gives exact solutions.