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  • Answer

    In general, we recommend using the English program interface if you want to create a printout report in English. Thus, the most should be displayed in English. However, this does not refer to terms previously created in German. These would have to be changed manually.

  • Answer

    No, that is not possible. The report can not be opened or managed via the COM Interface. The only thing that can be done is to access the number of created reports in a list.

    It is possible to access the report templates. This is explained in the following FAQ. However, this can not be controlled by the COM Interface of RFEM/RSTAB, but by a general Windows functionality.
  • Answer

    Yes, it is possible to integrate the complete frame 'Snow, Wind and Seismic Zone Maps' including the search function, location description and load output by means of the URL in other applications.

    After entering the "Full Screen" mode, you receive the required URL in the browser address bar.

    For determining the location-specific building loads, there is – additionally to this - an online web service in the background. If providing the necessary data (location, load type, load standard, etc.), this web service allows the data to be called up digitally for transfer to an external application.

    → see FAQ

  • Answer

    In order to recognize the cross-sections during the direct import of beams and columns in REVIT, the corresponding family must be available for such components in the REVIT project.
    If this is not the case, you can import the suitable family into your project during the import process. The interface then recognizes all other cross-sections itself and creates the corresponding cross-sections within the family.

    In Figure 01, a timber column 480/520 (mm) has not been found. After importing the correct family type, this cross-section and all other cross-sections of the same type are recognized and the import process is successfully completed.

  • Answer

    There are two options for the export to Advanced Steel (Figure 01):

    • Export via Product Interface

    Export the data in an stp format via the interface of the German Steel COnstruction Association and import this file to the target program.

    You can find this interface in the menu "File" → "Export" in the "Formats for Frameworks" section.

    • Export via Advance Steel Interface

    Export the data in an smlx format via the "Advance Steel" interface and import this file to the target program.

    You can also find this interface in the "Export" dialog box, under "General Formats for CAD Programs."

    Figure 01 - Export

  • Answer

    With the COM interface, you can access most operating elements as well as results of the following programs or add-on modules:

    • RF-/STEEL
    • RF-/STEEL EC3
    • RF-/TIMBER Pro
    • RF-/DYNAM Pro
  • Answer

    The student version also supports the interface to REVIT.
  • Answer

    • Interface between RFEM/RSTAB and Autodesk Revit

      RFEM and RSTAB communicate with Revit Structure via a direct interface and allow data to be exchanged. Structures modeled with RFEM and RSTAB can be transferred at the push of a button to Revit Structure.

      RFEM/RSTAB is based on an object-oriented building model and Revit on parametric modeling. Thus, the intelligence of the objects is not lost during the data exchange. This means that you get another equivalent object in Revit or RFEM/RSTAB for a column or beam, and not just a collection of lines.
    • Direct RSTAB/RFEM interface to Autodesk AutoCAD

      The members are exported as lines from RFEM/RSTAB. The layers of these lines contain information about the used cross-sections and materials. When exporting a DXF file from RFEM, it is possible to export the numbering, which is controlled by the navigator, in addition to the entire model - including the FE mesh.

      Another option for exporting from RFEM/RSTAB is to transfer results in the form of isolines to a DXF file. Various elements such as isolines, FE mesh, values, etc. can be specifically selected.

    • Direct RSTAB/RFEM interface to Tekla Structures

      With the directly integrated interface, the analytical model of detailed systems can be transferred easily from Tekla Structures to RFEM/RSTAB.

      The Tekla model can be updated quickly using the direct interface by comparing the modified materials, profiles and coordinates when carrying out modifications in structural engineering. It is also possible to remove construction elements that no longer exist or to add new ones.

    • Interfaces to Rhino & Grasshopper

      Rhino interface: Lines, as well as surfaces including openings, can be transferred to RFEM (export) or imported from RFEM (import). The following line types can be transferred: line, polyline, arc, circle, ellipse, parabola and NURBS. In addition, it is possible to exchange these surface types: plane, rotated surface, and NURBS.

      Grasshopper Interface: This interface enables activation of the Dlubal-Tab in Grasshopper. This includes three components. The 'Surfaces' component allows you to add Dlubal-specific surface properties (material, thickness, surface stiffness type) to 2D geometries. Use the 'Member' component to add member-specific properties (material, cross-section, member rotation) to incoming lines or curves. The third component allows for direct export to RFEM.

    • Other exchange formats

      DXF, IFC, STP (e.g. for Intergraph, Advance Steel, SEMA, Cadwork, HSB-Cad, etc.), DSTV (e.g. for Bocad and Frilo), FEM (Glaser) and CFE (Strakon), XLS (Microsoft EXCEL), CSV, ISM.DGN, DGN (Bentley ISM), DAT, SMLX (Advance Steel), ASF (Nemetschek Allplan), ESF

    A detailed overview of the interfaces and the BIM-oriented planning is available on our website Building Information Modeling (BIM).

    Also, there are already numerous webinars about BIM that you can watch on our website as a video.
  • Answer

    Unfortunately, there are two different interfaces with the same file extension - the .stp interface of the German Steel Construction Association (Deutcher STahlbau-Verband, DSTV) on one hand, and the STEP interface (STandard for the Exchange of Product model data) on the other hand, which is defined in the ISO standard 10303.

    While the DSTV interface refers to the system axes of members, that is to the structural model, the STEP interface refers to the model geometry in the form of boundary lines, surfaces and simple solids. In the latter case, the models can be imported either as RFEM objects (nodes, lines, surfaces, solids) or as background layers so that the nodes can be set manually. The STEP interface does not usually transfers any system lines, but only the outer contours of structural components so it is necessary to manually create system planes afterwards. You can do this in RFEM and RSTAB, for example, by using a CAD/BIM model.

    If you get the error message shown in Figure 01, you have tried to import an .stp file based on STEP using the DSTV interface. As described above, both formats are not compatible with each other.

    In this case, select the STEP format for the import, as shown in Figure 02. If a message shown in Figure 03 appears, it is because this interface requires the RF-LINK add-on module.

  • Answer

    In order to obtain the weld stresses, it is important to know which type of surface stresses resulting in RFEM are relevant. The figure shows a simple example: the clip fixed in the z-direction is subjected to a distributed load of 100 kN/m at the upper end in the x-direction and to a distributed load of 10 kN/m in the y-direction. 

    To determine the correct stresses, you have to know the local coordinate system of the surface. It can be activated in the Display navigator under 'Model → Surfaces → Surface Axis Systems x, y, z'. All stresses with '+' in the index represent the stress on the upper side, that is, the side of the positive local z-axis. When displaying the surface moments, it is necessary to pay attention to the fundamental difference between the surface and member internal forces: while the member moment My 'rotates' about the local member axis y, the surface moment my acts in the direction of the local surface axis y, that is, about the axis x of this surface. 

    For the given example, this means that my represents the bending moment of the clip in the direction of the global y-axis. Therefore, the resulting value must be 2 kNm/m. The average in the diagram shown in the figure confirms this with the value of 1.95 kNm/m (deviations can be reduced by a finer FE mesh). The average of the shear flow is 100 kN/m and thus corresponds to the applied load.

    Therefore, the stress σy,+ reflects the compressive stress of the clip on the upper side of the surface; τxy,x corresponds to the shear stress in the interface on the same side.

    The stresses should only be evaluated if the weld thickness is equal to the surface thickness. Otherwise, you should determine the stresses manually from the applied internal forces.

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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.

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