Да, это возможно.
Откройте окно «1.2 Материалы» и базу данных материалов для арматурной стали. (см. Рисунок 01).
In this material library, you can create a new "user-defined" material and edit the standard preset for the yield strength, for example. (см. рисунок 02).
Afterwards, you can select this user-defined material for design in Window 1.2 in RF‑CONCRETE Members and RF‑CONCRETE Columns.
It is the same for the RSTAB add-on modules CONCRETE and CONCRETE Columns.
In the settings for National Annex, there are the limits defined for the maximum value of the yield strength. См. рисунок 03. To change this limit, you need to create a new user-defined national annex. See Image 04.