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  • 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.

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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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