“…The analytical strategy employed here considers the possibility of polygonal cross-sections of various different materials in the same beam, and relies on a piecewise polynomial description of the uniaxial stress-strain relations. By means of a contouring algorithm and using Green's theorem, the area integrals are transformed into line integrals on the cross-section boundaries, see details as presented by Sousa and coworkers [30,31]. The main advantage of this strategy is the possibility of considering generic polygonal cross-section geometries, associated to a fast and exact evaluation of the cross-section properties.…”