Import of Stiffness Modifications
Tips & Tricks
In RF-/DYNAM Pro - Natural Vibrations, it is possible to import axial forces and stiffness modifications from any Load Case (LC) or Load Combination (CO). You can modify material, cross‑section, member and surface properties and activate those modifications in the LC/CO calculation parameters.
It is also possible to import stiffnesses from RF-/CONCRETE. Members or surfaces can be deactivated to analyze a modified structural system in RF-/DYNAM Pro. Axial forces and failing members are imported from the set LC/CO.
All stiffness modifications are initial conditions for the eigenvalue analysis performed in RF‑/DYNAM Pro. There, a linear calculation is performed.
When you want to consider axial forces only (for example prestress in cables or consideration of the P‑Delta effect) make sure that no stiffness modifications are activated in the calculation parameters of the imported LC/CO.
When you want to study certain stiffness modifications or deactivated members only, make sure you create a LC containing no loads but the stiffness modifications you are interested in.
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Frequently Asked Questions (FAQ)
- Why do I only obtain the seismic loads calculated in one direction in the case of design with RF‑/DYNAM Pro?
- During the check in RF‑/DYNAM Pro, I get the message "No natural vibration case or dynamic load case has been selected for the calculation." Why?
- Is it possible to display natural frequencies separately for each direction?
- What is the approach for seismic design in RFEM/RSTAB?
- What do the symbols mean in the graphical representation of the mode shapes of the RF-/DYNAM Pro add-on module?
- How is it possible to consider tension members in RF‑/DYNAM Pro?
- In RF-/DYNAM Pro, I get the error message: "The assigned mass case does not exist," although I have defined a mass case. What is the reason?
- In RF‑/DYNAM Pro, the "From self-weight of structure" option is available in a mass case. Is it always necessary to activate this option in order to consider the dead load of the structure?
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Add-on Module
Dynamic analysis of natural frequencies and mode shapes of member, surface, and solid models
1,030.00 USD
