What do I have to specify in the add-on module RF-/CONCRETE Columns and RF-/CONCRETE Members if the stability analysis of a frame system made of concrete needs to be a second order-analysis?
In RF-/CONCRETE Columns, the design is carried out using the method based on nominal curvature. When verifying the bending resistance, the program internally determines whether a normal design is enough or whether a second-order analysis of the moments is necessary. Therefore, you need to specify the load combinations for the design by using the option for the determination of the internal forces according to geometrically linear static analysis. Moreover, the program determines the eccentricity due to imperfections. Therefore, specify the load cases and combinations without imperfections.
In RF-/CONCRETE Members, the design can be done according to the general design method. Specify the load combinations with the option for the determination of internal forces using the second-order analysis. Also, consider the imperfections. Furthermore, a nonlinear calculation considering the cracked state is necessary.