The interaction of flexure and axial forces in singly and doubly symmetric shapes is governed by formulas of the Section 3.4 of the NTC. These interaction formulas cover the general case of biaxial bending combined with axial force. They are also valid for uniaxial bending and axial force.

It is considered that the frames are part of structures that have shear walls or rigid elements so that the lateral displacements of a floor could be disregarded. The program has included formulas to include structures with lateral displacements in the future considering for B2 the columns individually and not the complete floor analysis.

It is taken into account if the elements have transverse loads and if the ends are angularly restrained.