There are two type of analysis in EN 1993-1-1. Classification of cross sections is based on method of analysis. Capacity of cross sections is determined according to their classes.
Elastic structural analysis is based on the assumption that the stress-strain behavior of the material is linear. Elastic structural analysis resistances can also be used for cross sections restricted due to local buckling. According to EN 1993-1-1 5.4.2, elastic global analysis is be able to adapt despite the fact that class of cross section allows plastic deformations.
According to 5.4.3, plastic structural analysis is based on the nonlinear material behavior. The structural system behavior is modeled by one of the following methods:
Fully plasticized cross sections and / or as plastic hinges Elastic-plastic analysis with behaving joints
Nonlinear plastic analysis that takes into account partially plasticized structural elements in plastic areas
Rigid plastic analysis ignoring the elastic behavior between plastic joints