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2015-08-31

Quadratic Combinations SRSS and CQC as "Equivalent Linear Combination"

The modal results of a response spectrum analysis are combined with quadratic combination rules, and in RF‑/DYNAM Pro, the SRSS and the CQC rules are available. The default setting modifies the quadratic expressions into equivalent linear combinations. The advantage of this option is that the corresponding internal forces keep their signs and are often much smaller, compared to the standard SRSS or CQC rules. The standard SRSS and CQC rules are on the conservative side and the "equivalent linear combinations" are recommended.

The applied formulas are shown in the figure. It gives a specific example of this option when the SRSS rule is applied. It also works for the CQC rule.

Quadratic combinations, also in the form of the equivalent linear combinations, are available in RFEM and RSTAB and can be applied to any result combination. A license for RF‑/DYNAM Pro is not essentially required.

The "equivalent linear combination" was first published by Prof. Katz in the German journal D‑A‑CH‑Mitteilungsblatt.

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Export RFEM or RSTAB Models to *.glb or *.glTF Format

RFEM and RSTAB models can be saved as 3D glTF models (*.glb and *.glTF formats). View the models in 3D in detail with a 3D viewer from Google or Babylon. Take your VR glasses, such as Oculus, to "walk" through the structure.

You can integrate the 3D glTF models into your own websites using JavaScript according to the instructions (as on the Dlubal website Models to Download): "Easily display interactive 3D models on the web & in AR" .

Activation of Camera Flight Mode in RFEM

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.

"Update only Materials, Thicknesses, and Cross-Sections" Export Option

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.

Transfer of Reinforcement from RFEM/RSTAB (Top) to Revit (Bottom)

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.

Frequently Asked Questions (FAQ)

Where can I find the update reports for RFEM 5, RSTAB 8, SHAPE-THIN, SHAPE-MASSIVE, RX-TIMBER, CRANEWAY, PLATE-BUCKLING, COMPOSITE-BEAM?

For my NVIDIA graphics card, I need to select between a driver from the "Production Branch" and a "New Feature Branch." Which driver is best suited for RFEM/RSTAB?
Why do the min/max values of the total displacement not match the deformations when working with result combinations?
Can I display node coordinates in my model?
Can I use SHAPE-THIN 9 in combination with RSTAB 8?
Has the RF-TOWER add-on module for RFEM 5 already been added to RFEM 6?
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