Dynamic and Seismic Analysis Software

Vizualized mode shape of skyscraper in RFEM

3D Finite Element Analysis and Design

Structural engineering FEA software RFEM is the basis of a modular software system. RFEM is used to define structures, materials, and loads for planar and spatial structural systems consisting of plates, walls, shells and members. The program also allows you to create combined structures as well as model solid and contact elements.

Model of lattice tower in RSTAB

Analysis & Design of Frame/Beam/Truss Structures

Structural frame analysis and design software RSTAB contains a similar range of functions as RFEM, with special attention to frame and beam structures. Therefore, it is very easy to use and for many years it has been the best choice for structural analyses.

Mode shape of bridge

Determination of Natural Frequencies and Mode Shapes

RF-/DYNAM Pro - Natural Vibrations performs the analysis of natural frequencies and mode shapes.

Excitation case with harmonic loads

Analysis of Forced Vibrations

RF-/DYNAM Pro - Forced Vibrations performs the analysis of forced vibrations including the multi-modal response spectrum method and time history analysis.

Generated equivalent seismic loads

Generation of Equivalent Lateral Loads for Earthquakes

RF-/DYNAM Pro - Equivalent Loads generates equivalent lateral loads for earthquakes using the multi-modal response spectrum analysis.

RFEM/RSTAB Add-on Module RF-/DYNAM Pro - Nonlinear Time History | Nonlinear Time History Analysis

Nonlinear Time History Analysis

RF-/DYNAM Pro - Nonlinear Time History is an extension of the add‑on modules RF‑/DYNAM Pro - Natural Vibrations and RF‑/DYNAM Pro - Forced Vibrations (linear time history analysis).

Knowledge Base | Dynamic Analysis

  1. 1 - Reduction of building on cantilever structure. The individual mass points represent storeys. Displacement due to compression normal forces shown in (a) is converted to (b) overturning moments or lateral loads [2].

    Considering Second-Order Theory in Dynamic Analysis

    For the ultimate limit state design, EN 1998-1 Section 2.2.2 and [1] require the calculation considering the second-order theory (P-Δ effect). This effect need not be taken into account only if the interstorey drift sensitivity coefficient θ is less than 0.1. The coefficient θ is defined as follows:
    $$\theta\;=\;\frac{\displaystyle P_{tot}\;\cdot\;d_r}{V_{tot}\;\cdot\;h}\;(1)$$
    $\theta\;$ the interstorey drift sensitivity coefficient
    $P_{tot}$ the total gravity load at and above the storey considered in the seismic design situation (see Expression 2)
    $d_r$ the design interstorey drift, evaluated as the difference of the average lateral displacements $d_S$ at the top and bottom of the storey under consideration; for this, the displacement is determined by using the linear design response spectrum with q = 1.0
    $V_{tot}$ the total seismic storey shear determined by using the linear design response spectrum
    $h$ the interstorey height

  2. Signed Results Using the Dominant Mode

    Signed Results Using the Dominant Mode

    In RF-/DYNAM Pro - Equivalent Loads, a signed result option in accordance to the dominant eigenmode is available since version X.06.3039. For the modal combination of results corresponding to the single eigenvalues a quadratic combination rule has to be used, in RFEM and RSTAB the SRSS and the CQC rule are available. It is only allowed to combine results not loads directly. The reason are the mode shapes which are arbitrarly scaled and signed.

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Screenshots and Application Examples | Dynamic Analysis