Orthotropic bases and slats
Welded machine elements – Design and static calculation of welded components

Structures of this type, often in the shape of a flattened parallelepiped (a, b, h), consist of two flat footings joined by an orthogonal network of internal ribs that enable the assembly to resist biaxial flexion (M_x, M_y) generally produced by uniform pressure and/or concentrated forces exerted on the footings (figure 50). The internal ribs are arranged at pitches (c, d) respectively with respect to each of the main x, y directions. When the baseplate is subjected to uniform pressure and/or concentrated forces arranged symmetrically with respect to center 0, it is desirable for the pitches to be the same: c = d.