The combination expression is based on the selected standard. This standard can be Eurocode 0, for example.
To create various design situations, such as the ultimate limit state, serviceability limit state, fire situation or earthquake, different combination expressions are required. The individual combination expressions are based on various probabilities, which are adapted for the respective purpose of the design.
Entering in RFEM and RSTAB
If there is a standard set for the classification of load cases and combinations in General Data of the model and the option for the automatic creation of combinations is also selected, result combinations or load combinations are created on the basis of the combination expressions. If the option for the automatic creation of combinations is disabled, there are no combination expressions set up in the program and you need to create the combinations manually.