We provide hints and tips to help you get started with the main programs RFEM and RSTAB.
The equivalent loads that are exported into Load Cases in the main program RFEM / RSTAB are evaluated with consideration of all nonlinearities, in some cases this can lead to conflicts. An example is illustrated in the picture. In the first case no stiffness modifications are used in RF-/DYNAM Pro and therefore all members are considered in the dynamic analysis, but in RFEM / RSTAB the tension member fail due to equivalent loads. When you want to perform a completely linear analysis you must deactivate the nonlinearities in RFEM / RSTAB. In the second and third illustrated case an initial condition is imported where the tension members are not available. The equivalent loads are therefore based on the same structure as the structure for the calculation of internal forces and deformations.
In the response spectrum analysis or the time history analysis with the add-on module RF-/DYNAM Pro Forced Vibrations the modified stiffness of the Natural Vibration Cases (NVCs) is also used for the calculation of further results. The overall linear analysis with consideration of initial conditions is performed within the module RF-/DYNAM Pro.
Tension members, nonllinear, nonlinearities, dynamic