Combined direct and bending stress
Bending in struts and ties A number of situations arise in structural systems where the members become subject to a combination of direct (axial) and bending stresses acting parallel to the longitudinal axis. Such members may, for convenience, be considered as either struts or ties resisting direct stress primarily but which, in addition, must also resist longitudinal stresses resulting from bending moments. These bending moments may be induced in a number of different ways: (a) due to an externally applied moment, (b) due to the longitudinal loading being applied eccentrically with
reference to the centroidal axis of the section, (c) due to the member buckling.