In RFEM/RSTAB, you define several load cases containing the loads in the desired position. In RF‑/DYNAM Pro - Forced Vibration, you define the same amount of time diagrams. And in dynamic load cases, you combine all those together.
The loads in load cases can be of nearly any type: nodal, member, surface, free, or generated loads. Time diagrams can be defined as periodic, transient, or directly as function. The figure shows an example of walking on a simple supported beam.
Knowledge Base
Knowledge Base
Customer Project
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 behavior correctly, at least two FE layers for gas solids should be defined.
Calculation with consideration of a damping ratio (or Lehr's damping) is not possible in the direct time step integrations. Instead, the Rayleigh damping coefficients must be specified by the user.
In technical literature, the given damping ratio for specific construction forms is, in many cases, only a rough approximation of the real damping ratios. In RF-/DYNAM Pro - Forced Vibrations, it is possible to use the value of the damping ratio to determine the Rayleigh damping. This may occur at one or two natural angular frequencies defined by the user.
The member type 'Dashpot' can be used for time history analyzes in RFEM/RSTAB with the add-on modules RF-/DYNAM Pro - Forced Vibrations and RF-/DYNAM Pro - Nonlinear Time History. This linear viscous damping element considers forces dependent on velocity.
With regard to viscoelasticity, the member type 'Dashpot' is similar to the Kelvin-Voigt model, which consists of the damping element and an elastic spring (both connected in parallel).
Main Program
The new generation of 3D FEA software is used for the structural analysis of members, surfaces, and solids.
Add-On
The Modal Analysis add-on allows for the calculation of eigenvalues, natural frequencies, and natural periods for member, surface, and solid models.
Add-On
The Response Spectrum Analysis add-on performs seismic analysis using multi-modal response spectrum analysis. The spectra required for this can be created in compliance with the standards or can be user-defined. The equivalent static forces are generated from them. The add-on includes an extensive library of accelerograms from seismic zones that can be used to generate the response spectra.
Add-On
Using the Pushover Analysis add-on, you can analyze the seismic actions on a particular building, and thus assess whether the building can withstand an earthquake.
Add-On
The Time-Dependent Analysis (TDA) add-on allows you to consider the time-dependent material behavior of members. The long-term effects, such as creep, shrinkage, and aging, can influence the distribution of internal forces, depending on the structure.
Add-On
The Concrete Design add-on allows for various design checks according to international standards. You can design members, surfaces, and columns, as well as perform punching and deformation analyses.
Add-On
The Steel Design add-on performs the ultimate and serviceability limit state design checks of steel members according to various standards.
Add-On
The Timber Design add-on performs the ultimate, serviceability, and fire resistance limit state design checks of timber members according to various standards.
Add-On
The Masonry Design add-on for RFEM allows you to design masonry using the finite element method. It was developed as part of the research project titled DDMaS – Digitizing the Design of Masonry Structures. The material model represents the nonlinear behavior of the brick-mortar combination in the form of macro-modeling.
Add-On
The Aluminum Design add-on performs the ultimate and serviceability limit state design checks of aluminum members according to various standards.
Main Program
The modern 3D structural analysis and design program is suitable for the structural and dynamic analysis of beam structures as well as the design of concrete, steel, timber, and other materials.
Add-On
The Modal Analysis add-on allows for the calculation of eigenvalues, natural frequencies, and natural periods for member, surface, and solid models.
Add-On
The Response Spectrum Analysis add-on performs seismic analysis using the multi-modal response spectrum analysis. The spectra required for this can be created in compliance with the standards or can be user-defined. The equivalent static forces are generated from them. The add-on includes an extensive library of accelerograms from seismic zones that can be used to generate response spectra.
Add-On
Earthquakes may have a significant impact on the deformation behavior of buildings. A pushover analysis allows you to analyze the deformation behavior of buildings and compare them with seismic actions. Using the Pushover Analysis add-on, you can analyze the seismic actions on a particular building, and thus assess whether the building can withstand the earthquake.
Add-On
Concrete Design add-on allows for various design checks of members and columns according to international standards.
Add-On
The Steel Design add-on performs the ultimate and serviceability limit state design checks of steel members according to various standards.
Add-On
The Timber Design add-on performs the ultimate, serviceability, and fire resistance limit state design checks of timber members according to various standards.
Add-On
The Aluminum Design add-on performs the ultimate and serviceability limit state design checks of aluminum members according to various standards.
![Reduction of Building to Cantilever Structure: The individual mass points represent the floors. The deflection due to the normal compression forces shown in (a) is (b) converted into equivalent moments of displacement or shear forces [2].](/en/webimage/009762/2420261/01-en-png-12-png.png?mw=350&hash=dd36dc43123116724231958668ad6cdcb13a0169)
