The bending force can be a result of external loads, weight, or the length of the beam. The beams experience a bending moment and a shear moment due to these loads.

Beams are typically loaded by concentrated forces, distributed forces, and concentrated moments. Typical beam supports include pinned supports, roller supports, and fully fixed supports.

M. R. Horne, The Plastic Theory of Bending of Mild Steel Beams with Particular Reference to the Effect of Shear Forces, Proceedings of the Royal Society of London. Series A, Mathematical and Physical ...