Accelerograms are considered as the actions on structures that are applied to the supports of the structure and thus excite the structural system to vibrations. These actions are calculated by using the time history analysis.
Furthermore, accelerograms allow you to generate response spectra or use them directly in the response spectrum analysis.
Entering in RF-/DYNAM Pro
Accelerograms can be entered in RFEM or RSTAB by using the RF-/DYNAM Pro add-on module. The data can be imported from a library that contains a large number of earthquake records (see Figure 01). You can also create a user-defined diagram or import it from Excel (see Figure 02). It is possible to enter the data separately for all three directions (X, Y and Z).
With RF-/DYNAM Pro Equivalent Loads, it is possible to perform an equivalent load calculation using the multimodal response spectrum method. In the example shown here, this was done for a multi‑mass oscillator.
Connecting Static Load Cases with Time Diagrams for Time History Analysis in RF-/DYNAM Pro - Forced Vibrations
Import of Axial Forces, Stiffness Modifications and Extra Options in RF-/DYNAM Pro - Natural Vibrations
The stiffness of gas given by the ideal gas law pV = nRT can be considered in the nonlinear dynamic analysis.
The calculation of gas is available for accelerograms and time diagrams for both the explicit analysis and the nonlinear implicit Newmark analysis. To determine the gas behaviour correctly, at least two FE layers for gas solids should be defined.
- After calculating the add -on module RF-/DYNAM Pro - Equivalent Loads, the size of my file has increased significantly. The performance has deteriorated enormously. What could be the reason for this?
- I would like to calculate and design "temporary structures." What do I need for this?
- Which programs can I use to calculate and design power plants?
- I noticed deviations from the map of DIN EN 1998‑1 or DIN 4149 in the online service "<a href="https://www.dlubal.com/en-US/solutions/online-services/snow-load-wind-speed-and-seismic-load-maps" target="_blank">Geo-Zone Tool: Snow, Wind, and Seismic Zone Maps</a>." Can you tell me which map is current and thus governing?
- How do you distinguish between the response spectra with equivalent loads and the response spectra without equivalent loads in RFEM and RSTAB?
- What should be considered when using a failure of columns under tension in the RF‑/DYNAM Pro - Equivalent Loads add-on module?
- I would like to design an aluminum or lightweight structure. Is it possible to use RFEM or RSTAB for this?
- Why do I only obtain the seismic loads calculated in one direction in the case of design with RF‑/DYNAM Pro?
- Are the models and presentations from Info Day 2020 freely available, and can you send them to me?
- 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?
Structural engineering software for finite element analysis (FEA) of planar and spatial structural systems consisting of plates, walls, shells, members (beams), solids and contact elements
The structural engineering software for design of frame, beam and truss structures, performing linear and nonlinear calculations of internal forces, deformations, and support reactions
Dynamic and seismic analysis including time history analysis and multi-modal response spectrum analysis