Internal forces used for the superposition are calculated individually for the included load cases or combinations.
By applying various combination expressions, it is possible to generate an envelope of the distributions of internal forces by means of a result combination.
The result combination is not suitable for nonlinear calculations since the individual internal forces of load cases or load combinations are calculated for different structural systems (based on nonlinear effects, such as a failure of supports, members and releases).
Entering in RFEM and RSTAB
Result combinations can be entered and defined in RFEM and RSTAB graphically by clicking "Insert" → "Load Cases and Combinations" → "Result Combinations" or the corresponding button, or in tables using the Data navigator.