Load limit of a complete flange
The basic equations of EN 1591

The stress distribution in equation 9.1 is determined in the same way as in a limit analysis: the entire cross-section is assumed to be plasticized. This zone is then defined by a compression zone and a tension zone. Z ₀ is the dimension where the tangential stress changes from + S _F (respectively – S _F ) to – S _F (respectively + S _F ).

We rewrite equations 7.2 and 7.3, introducing 9.1 to obtain 9.2 and 9.3.