Technical Article: Determination of Critical Load Factors Using Structure Stability Add-on in RFEM 6 and RSTAB 9

Using the Timber Design add-on, timber column design is possible according to the 2018 NDS standard ASD method. Accurately calculating timber member compressive capacity and adjustment factors is important for safety considerations and design. The following article will verify the maximum critical buckling strength calculated by the Timber Design add-on using step-by-step analytical equations as per the NDS 2018 standard including the compressive adjustment factors, adjusted compressive design value, and final design ratio.

Rolled sections, the most common cross‑section type in RFEM and RSTAB, can also have user‑defined parameters. To do this, select the cross‑section to be modified in the cross‑section library and click the [Parametric Input...] button.

In this article, the adequacy of a 2x4 dimension lumber subject to combined biaxial bending and axial compression is verified using the RF-/TIMBER AWC add-on module. The beam-column properties and loading are based on example E1.8 of AWC Structural Wood Design Examples 2015/2018.

With the Camera Fly Mode view option, you can fly through your RFEM and RSTAB structure. Control the direction and speed of the flight with your keyboard. Additionally, you can save the flight through your structure as a video.

The direct interface with Revit allows you to update the Revit model according to the changes you have made in RFEM or RSTAB. Depending on the modification, the Revit objects may have to be regenerated (deleting the object and subsequent regeneration). The regeneration is performed on the basis of the RFEM/RSTAB model.

If you want to avoid this regeneration, activate the check box 'Update only materials, thicknesses, and sections'. In this case, only the properties of the objects will be adjusted. Changes different from those in material, surface thickness, and section are, however, not considered in this case.

The reinforcement proposal from RF-/CONCRETE Members can be exported to Revit. The rectangular and circular cross-sections are currently supported.

The reinforcement bars can be modified retroactively in Revit.