Three-Dimensional FEM Beam Elements

Finite Element Method's (FEM) beam elements are so far one-dimensional and mostly based on hypotheses of rigid and plane (not warping) cross sections. The advantages of those elements are their computational efficiency and their formulation based on the Strength of Materials theory. There are limitations, however, of using such elements (even with accounting for cross section's warping) along with multi-dimensional FEM elements in contemporary complex three-dimensional structures' FE models. This paper presents new developments, which objective is to have all kinds of three-dimensional FEM beam elements (solid and thin-walled) with variable number (as needed) of nodal points and degrees of freedoms and being capable of working with all kinds of FEM elements in three-dimensional structures FEM models, while still having the advantage of one-dimensional beam elements computational efficiency.