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  • Answer

    Depending on the geometric requirements of the bricks, these are integrated into classes 1 - 4. All geometric requirements for the brick classes are listed in Table 3.1 of the EN 1996-1-1. An example of assigning the classes according to the total percentage of the brick holes (% of the gross volume) is as follows:

    Class 1 (all stones)
    ≤ 25

    Class 2
    vertical hole ratio> 25; ≤ 55

    Class 3
    vertical hole ratio ≥ 25; ≤ 70

    Class 4
    horizontal hole ratio> 25; ≤ 70

  • Answer

    Edge-strand bonding is applied when the bricks of a wall are not laid on one mortar strip but on two. Apply the mortar to the outer edges of the bearing surfaces of the bricks.

    The application of the National Annex is governed by the question whether you can apply boundary strip bonding in a European country. The construction of masonry by edge strip cementing is excluded in the German National Annex. For this reason, the foundation joints in Germany must always be mortared over the entire surface.

  • Answer

    Yes, this is possible with a combination scheme. This can be used to create user-defined templates.

    The Combination Schema dialog box can be accessed via the "Tools" menu. A scheme defined there can be used as template for your load data. You can create a combination scheme in any model and access it from any model.

    In a combination scheme, you specify the load cases, load and result combinations to be created with the relevant key data and the basic settings. In addition to the number of load cases, load combinations and result combinations, you can also define the factors and the type of superposition in a combination scheme.

    Then, when creating a new model, you can quickly access these settings so that you only have to enter the contents of the load cases (member loads, etc.). If you have already created several schemes, you can select one of them from the pull-down list.

    Click the [New Scheme] button to create another combination scheme. In doing so, you can copy the existing load cases and combinations of the current model.

    The button [Create Load Cases, Load Combinations, and Result Combinations Defined in Tables] transfers the current combination scheme to the model.

    The combination diagrams can also be exported to Excel and reimported.

    The user-defined combination diagrams are stored in the KombinSchema.dat file, which is located in the master data folder "C:\ProgramData\Dlubal\Global\Root File" by default. If you copy this file to another computer, you can also use the combination diagrams there.
  • Answer

    This cross-section is a Parameterized I-Section; it can be entered in the cross-section library. In addition to the parametric thin-walled cross-sections (see Figure 1), for which information about the weld is generally required, the parametrized cross-sections are oriented to the rolled cross-sections.

    Parametrization is possible for some of the rolled cross-sections (see Figure 2). This allows you to define e.g. parameters for the fillet radius, the flange thickness, and for the web thickness. To avoid opening the graphical user interface of the cross-section parameters in case of changes, it is also possible to adjust the cross-section dimensions directly in the text box of the cross-section. If a change was made, the cross-section is updated immediately in the background.
  • Answer

    For lightweight structures, there are many technical membranes.

    • Polyester fabric (PES) coated with polyvinyl chloride (PVC) → PES/PVC
    • Polyester coating covered with Polyvinyl Chloride (PVC)
    • Glass fabric → Glass/PTFE, coated with polytetrafluoroethylene (PTFE)
    • Polyester Fabric (PES) coated with Polyolefin
    • Polyester fabric (PES) coated with fluoroplastic 
    • Glass fabric coated with silicone
    • Open and closed mesh fabrics
    • Uncoated and natural fabrics
    • Ethylene-tetrafluoroethylene foils → ETFE
    Depending on the various properties, RFEM selects these materials for the respective project for each structural task. With regard to the structural analysis, all products have different load-bearing properties, some of which can vary with each production batch.

    In RFEM, you have to enter these different values in material table 1.3 in connection with an appropriate material model.

    There are model templates for the recurring use of materials in different models. Any selected list of membrane materials can be stored and loaded directly when opening a new model. 

    In most cases, membrane materials always consist of an interaction of solid material values and a material law. Since the existing material library only organizes materials with the material law “Isotropic Linear Elastic”, this database is not applicable for orthotropic membrane materials.

  • Answer

    The processing time can be deleted in the history of the model. To do this, select the relevant model in the Project Manager and select the "History" command from the context menu. In the window "History of the model" click on the button "Delete" and confirm the entry with "OK" (see picture 1). In addition to the processing time, the information Created on, Created by, Changed on, and Changed by is also deleted.
  • Answer

    The diagrams are stored in a configuration file. For a standard installation, this file is located in the file path C: \ ProgramData \ Dlubal \ Global \ General Data \ and has the file name NonLinWorkDiagMembRelease.cfg. Before the configuration file is copied, the RFEM / RSTAB file must be saved and RFEM / RSTAB must be closed.

  • Answer

    You can start the project manager via the program RX-TIMBER or via the PRM64.exe.
    Assuming a standard installation, the exe for RFEM is available at: C:\Program Files\Dlubal\RFEM 5.xx

    and for RSTAB under: C:\Program Files\Dlubal\RSTAB 8.xx

    The RX-TIMBER program always starts via the project manager.

  • Answer

    The easiest way is to start RFEM or the add-on module RF-LAMINATE and create at least one surface and at least one load case. After you have selected the surface and defined the load case for calculation, open the manufacturer's library (see Figure 1). There you can select a structure.

    Afterwards you can check the material characteristics as well as the strengths (see picture 1 and picture 2).

    There is already an interesting webinar on the topic of Design of cross laminated timber panels in RF-LAMINATE on our website.

  • Answer

    Sometimes it may happen that the information window has moved all the way down (see picture).
    You can move this upwards with the left mouse button pressed.

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