Frequently Asked Questions (FAQ)

Search FAQ

Customer Support 24/7

Knowledge Base

In addition to our technical support (e.g. via chat), you’ll find resources on our website that may help you with your design using Dlubal Software.


Receive information including news, useful tips, scheduled events, special offers, and vouchers on a regular basis.

  • Answer

    Yes, the data is freely available. You can find the structures in the download section of this FAQ.
  • Answer

    The Dlubal toolbar is available to the user after carrying out a successful installation of the interface. Use the corresponding components to control the export to RFEM. To do this, simply drag and drop them into the programming interface. An import from RFEM is not possible.

    Communication between Grasshopper and RFEM is enabled by the 'RFEM 5 COM Component'. Once this component with geometric information is activated, the export is started. An opened RFEM file is supposed. It is also recommended to use an empty file because the export procedure overwrites or deletes all information. An update mechanism is currently not implemented.
    The 'RFEM 5 Member Component' allows the user to attach additional information to the geometry (lines, curves). These are taken into account when exporting to RFEM so that the members can be created. The name of material and cross-section has to be entered in a text box (panel). The member rotation can be defined by means of a 'Number Slider' in [rad].
    The 'RFEM 5 Surface Component' is to be used analogously to the 'Member' component. There is supposed a surface when entering the geometry. Using a panel, it is possible to attach the material to them. The thickness of the surface is defined by a number slider in [m]. The stiffness type of the surface can be controlled by means of a 'Value List' with predefined types.

    The Grasshopper file relating to graphic has been saved for download. You only have to define the connecting lines for the final export.

  • Answer

    In principle, the handling of the interface is very simple. After carrying out a successful installation, the Dlubal toolbar is available in Rhino. This includes two icons (Export and Import).

    Using 'Import', it is possible to import data from RFEM to Rhino. It is always imported the whole RFEM model. No update shall be performed in this case. The data is added to the existing structure.
    Click 'Export' to export data from Rhino to RFEM. Normally, the entire structure is exported. If you only want to export parts of the structure, select them before starting the export. It is necessary to start the RFEM and create a file to carry out the export. Please note that the export procedure overwrites all existing data of the opened file. Therefore, it is recommended to open an empty file.

  • Answer

    Please make sure that Rhino (version 6.20 or later) is already being installed. Then carry out the RFEM 5 installation. For this, you need at least version 5.21.02. The plug-ins are automatically saved in one of the following directories and installed during the installation.

    C:\Program Files\Common Files\McNeel\Rhinoceros\6.0\Plug-ins\

    Figure 02 - Directory of Plug-ins

    After completing the installation, Rhino and Grasshopper can be started. In both programs, the Dlubal-specific toolbars should be available by now. It is possible to attach the Dlubal Toolbar for Rhino to the other toolbars also retroactively (see video).

    Figure 01 - Dlubal Toolbar

    If Rhino has been installed later than RFEM, the interface is not available. In this case, it is recommended to perform a reinstallation of the RFEM.

  • Answer

    Yes, it is possible. For this, it is necessary to include the members in a set of members. For continuously connected members, you can use the "Continuous member" type. For other members, use "Group of members." Generally, the distinction is only important for subsequent design in add-on modules.
    After creating the sets of members and the structure, you can display the resulting internal forces in the result window "Sets of Members - Internal Forces." Use the table filter to hide the unwanted results.

  • Answer

    First, you should check if there is possibly a specific interface for the design program. If you use Revit or Tekla, the direct interfaces are available. There is also the option to export to the DSTV format. This is also supported by many programs.

    Of course, the export to the *.dxf format is possible at any time. Since member structures are basically pure central axis models with the information about cross-section and material attached, you can only export the lines.
    However, if you need a member as a 3D object, you can use the export into the Bentley ISM format. Please note that this requires the free Bentley Structural Synchronizer. You can find a link to this product at the end of this FAQ. The export can be easily run by clicking "File" - "Export."

    Structural Synchronizer converts members into solid models. Then, a file with the *.ism.dgn extension is recorded. This format is supported by many design programs.

  • Answer

    By default, the event log files that record the actions during the import or export can be found in the following folder:


    In most cases, there are several log files in this folder. If you want to open the log of the last data exchange, it is recommended to sort the files by the modification date. You can open the logs themselves by using an editor or WordPad, for example.
  • Answer

    The tolerance epsilon can be found in the FE mesh settings in the "General" section of the dialog box. It controls the behavior of the FE mesh generator when nodes are very close to lines. Figure 03 shows the difference. If the tolerance is greater than the distance of a node to a line, this small local difference in the mesh generation is neglected. In the case shown, the mesh of the line is deflected towards the node. In this case, the line is not ideally straight anymore. If the tolerance is smaller than the distance, a separate FE node is generated for the node.

    The error message appears if the distance between two adjacent nodes is smaller than epsilon and they are connected by a line (see Figure 03). In most cases, this is due to an inaccuracy in the modeling. Since the error message contains no information about the node numbers, you can use the "Identical Nodes" model check. The program searches for the nodes whose distance meets the tolerance delta. Now, you can set the tolerance value to the value of epsilon. Tthe nodes are then listed in the upper part of the dialog box.

    As described below, the descriptions differ depending on the case. If there is an inaccuracy in the modeling, it can be adjusted. In other cases, it is possible to further reduce the tolerance of epsilon, of course.

  • Answer

    Dlubal parameters are the parameters in Revit that do not exist by default. They are only enabled after the activation ("Add Parameters" → "Start") in various dialog boxes. 
    In this case, the information is specific to RFEM/RSTAB and can be stored in Revit. When exporting from Revit to Dlubal Software, you can export and convert this information from RFEM/RSTAB.

    "Without Tension"
    - to be found in the analytical wall properties
    - corresponds to the "Without membrane tension" surface type stiffness

    "Surface Support"
    - to be found in the analytical slab or plate properties
    - creates a surface support with the specified spring constants in RFEM

    "Dlubal Name (Material)"
    - can be found in the user-defined material parameters
    - possible to directly assign the Dlubal material name (without using the conversion table)

    "Dlubal Name (Cross-Section)"
    - to be found in the model properties of columns or beams
    - possible to directly assign the Dlubal cross-section name (without using the conversion table)

    "Member Type Truss/Tension Member"
    - to be found in the analytical beam or support properties
    - corresponds to the Truss or Tension member type in RFEM/RSTAB
  • Answer

    The interface between Dlubal Software and Revit works internally with so-called Global Unique Identifiers (GUIDs). In Revit, a GUID is assigned to each object. During the import and export, this GUID is transferred via the interface and added to the corresponding Dlubal Software object (member, surface, and so on). By using GUIDs, you can carry out updates in both directions with only those objects to be updated that are affected by the changes. Other objects remain unaffected. This results in a better compatibility during the data exchange.

    The comparison assumes that each object in Revit has a corresponding counterpart in the Dlubal Software application. For example, Revit treats each line support individually. If a line support type is assigned to several lines in RFEM, the line support type is automatically duplicated when exporting to Revit in RFEM. A line is assigned to each duplicate. Then, a 1:1 comparison is possible (see the figure).

    Due to the described functionality of the interface with the resulting modification of the Dlubal Software model data, it cannot be excluded that the results may be deleted. Therefore, it is recommended to export the model to Revit before the calculation. The results can be transferred retroactively within the second export process. 

1 - 10 of 15

Contact us

Contact Dlubal Software

Did you find your question?
If not, contact us via our free e-mail, chat, or forum support, or send us your question via the online form.

(267) 702-2815

First Steps

First steps

We provide hints and tips to help you get started with the main programs RFEM and RSTAB.

Wind Simulation & Wind Load Generation

With the stand-alone program RWIND Simulation, wind flows around simple or complex structures can be simulated by means of a digital wind tunnel.

The generated wind loads acting on these objects can be imported to RFEM or RSTAB.

Your support is by far the best

“Thank you for the valuable information.

I would like to pay a compliment to your support team. I am always impressed how quickly and professionally the questions are answered. I have used a lot of software with a support contract in the field of structural analysis, but your support is by far the best. ”