2. Cutting force

For a long time, the method used to calculate shear reinforcement was the so-called "Mörsch lattice" method, in which the compressed concrete rods are assumed to be inclined at 45°.

As tests have shown that oblique cracks cutting through compressed concrete "rods" can, at the moment of shear failure, have an inclination significantly less than 45° (a phenomenon highlighted as early as 1957 by René CHAMBAUD), this latter finding has been taken into account in EC2, where the method used is known as "variable rod inclination".