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  • Answer

    The following reasons may affect the processing time of the "Update Navigator" intermediate step:

    Interference of Virus Scanner (most common cause)
    Please adjust the exceptions of the virus scanner to speed up your work with RFEM:

    Interaction with Multimedia Driver (rare)
    In rare cases, the interaction with the multimedia driver can increase the processing time. This problem can be solved by upgrading Windows with MediaCreationTool1909.
  • Answer

    No, the calculation time is not affected, because the data is copied to the local working directory when loading, and is only rewritten after saving them. Depending on the connection speed to the server, delays may occur during loading and saving.
  • Answer

    In the case of long crane runways and many cranes, the large number of load combinations can lead to a long calculation time. The following settings affect the calculation time significantly:

    Calculation Method for Determining Internal Forces
    • Fast calculation (a calculation of all load combinations according to the linear static analysis, then a calculation of the governing load combinations according to the second-order torsional buckling analysis)
    • Detailed calculation (a calculation of all load combinations according to the second-order torsional buckling analysis)
    The fast calculation type may therefore be useful for preliminary design.

    Maximum Target Length of Finite Elements
    The maximum length of the finite elements generated for the calculation according to the second-order torsional buckling analysis can be entered within the range of 100 mm to 2,500 mm. The calculation time can be increased significantly by the finer division of finite elements.
    Thus, you should select a reasonable length of the finite elements for an optimized calculation time, depending on the structural system. Usually, 8 elements for each girder span are enough to calculate the deformations with a deviation of less than 5% with regard to a precise solution.

    Number of Load Combinations
    You can use a reasonable setting of the load increment to control the number of generated load combinations. When entering the load increment, the generated number of crane load positions and load combinations is already displayed in a preview. A small load increment may result in many load combinations that take more time in the calculation accordingly.

  • Answer

    Generally, in order to optimize or minimize the time required for all processes in the case of large models, you should pay attention to various points. It might be useful to

    • use the wireframe model in the graphic instead of the solid model,
    • deactivate the display of tables and the navigator,
    • add our programs to the exceptions in the settings of your antivirus program,
    • have as few applications and RFEM/RSTAB files as possible opened at the same time,
    • upgrade your PC. For example, you can often achieve a significant performance increase with an SSD memory. Your PC should also have sufficient RAM memory.
    Furthermore, generated loads can also negatively affect the performance as they are recalculated in the background after each work step. If there is a lot of them in the model, it may sometimes be useful to disconnect them (see Figure 02). However, the big advantage of adjusting the loads automatically in the case of any changes in the model will be lost.

    It may also be helpful to save the RFEM/RSTAB files locally instead of in a network.

    A possible cause of the slower reactions of the program may be missing user rights. If you are not working with the administrator account, it is necessary to have full access rights to various directories and subdirectories.

    Furthermore, you should ensure that you always work with the current version of RFEM/RSTAB.

  • Answer

    The speed of the printout report depends primarily on the amount of data you want to print. If many pages are printed, a delay is likely.
    The number of graphics to be printed and, in particular, the graphic resolution are also crucial.
    When printing on a DIN A4 format, it makes little sense to print the graphics with the maximum resolution (5000 x 5000 pixels), especially since they require a file size that is 25 times higher than the standard resolution (1000 x 1000 pixels).
    When working in the printout report, the main access point is the printer driver set as default in the control panel of the operating system.
    If they are outdated or faulty, delays may occur as well. In this case, it makes sense to select a different printer than the default one.
    In particular, virtual printers such as PDF24 often result in a significant increase in performance.

  • Answer

    If you want to move graphics or delete, add or modify chapters, you should deactivate Immediate Refresh of the preview (see the figure).
  • Answer

    Until RFEM 5.07.11 there was a problem with multi-core processors - eg Intel XEON.

    Please exchange and try the two files attached to this FAQ on the problem computer.

    Folder Program Files / Dlubal / RFEM 5.07 or Program Files / Dlubal / RFEM 5.07

  • Answer

    The very time-consuming design in STEEL EC3 and Aluminum can be caused by the cross-sections of the "General" type.

    These can be seen in Window 1.3 Cross-Sections. For these cross-sections, it is necessary to calculate the stresses for the cross-section classification with SHAPE‑THIN in the background. The result combination (RC) for the design may contain a lot of load combinations (CO), which is why the SHAPE‑THIN calculation is performed very often and takes a very long time. However, there is a workaround. With the option shown in the second figure, the enveloping internal forces of the RC are used, and not every CO contained in the RC is calculated. Although this may be more conservative, it is faster because not every CO requires the SHAPE‑THIN calculation, but only the envelope.

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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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