3D beam element based on Saint Venànt’s rod theory

The paper deals with the use of Saint Venànt’s general rod theory for deriving the stiffness matrix for 3D beam elements with general cross-section. The elastic factors of the section are obtained through the numerical solution of the Saint Venànt differential equations. Different discretization strategies have been investigated including FEM and BEM alternatives the one based on 6-node triangular elements appears to be the best choice.