Torsional Warping (7 DOF) for RFEM 6 / RSTAB 9

Product Description

  • Add-on Module of Category "Other"

Consideration of Cross-Section Warping as Additional Degree of Freedom



  • Consideration of the 7th degree of freedom directly in the RFEM/RSTAB model (thus, real consideration of the stiffnesses of the connected elements)
  • No need to define the equivalent spring stiffness or support conditions for a separated structural system
  • Determination of critical load factors and mode shapes for lateral-torsional buckling (in combination with the Stability Analysis add-on)
  • Structural calculation according to geometrically linear, second-order, and large deformation analysis
  • Possible to consider imperfections and stiffness reduction
  • Using internal forces from the calculation with warping torsion in the design add-ons

Do you want to calculate members? The '''Torsional Warping (7 DOF)''' add-on allows you to consider the cross-section warping as an additional degree of freedom when calculating members in RFEM and RSTAB. This provides you with more options.



  • Consideration of 7 local deformation directions (ux, uy, uz, φx, φy, φz, ω) or 8 internal forces (N, Vu, Vv, Mt,pri, Mt,sec, Mu, Mv, Mω) when calculating member elements
  • Usable in combination with a structural analysis according to linear static, second-order, and large deformation analysis (imperfections can also be taken into account)
  • In combination with the Stability Analysis add-on, allows you to determine critical load factors and mode shapes of stability problems such as torsional buckling and lateral-torsional buckling
  • Consideration of end plates and transverse stiffeners as warping springs when calculating I-sections with automatic determination and graphical display of the warping spring stiffness
  • Graphical display of the cross-section warping of members in the deformation
  • Full integration with RFEM and RSTAB


  • You can activate or deactivate the use of torsional warping in the Add-ons tab of the model's Base Data.
  • After activating the add-on, the user interface in RFEM is extended by some new entries in the navigator, tables, and dialog boxes.


You can perform the calculation of the warping torsion on the entire system. Thus, you consider the additional 7th degree of freedom in the member calculation. The stiffnesses of the connected structural elements are automatically taken into account. It means, you don't need to define equivalent spring stiffnesses or support conditions for a detached system.

You can then use the internal forces from the calculation with warping torsion in the add-ons for the design. Consider the warping bimoment and the secondary torsional moment, depending on the material and the selected standard. A typical application is the stability analysis according to the second-order theory with imperfections in steel structures.

Did you know? The application is not limited to thin-walled steel cross-sections. Thus, it is possible for you, for example, to perform the calculation of the ideal overturning moment of beams with solid timber cross-sections.

Online Manual | Torsional Warping (7 DOF)



1,650.00 EUR

The prices apply to the use of the software in all countries.

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