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  • Answer

    The RWIND Simulation program is protected against unauthorized use. If the software key is authorized, the program is only authorized for a specific activation period, which must be defined by the user. After this period, the program automatically switches to the demo mode; the previously used license is freely availablea gain for a new activation. To avoid the reactivation on the same single‑user computer, it is possible to renew the license online (a computer is connected to the Internet) by specifying a new activation period before the activation period expires. Proceed as follows:

    1. Run RWIND Simulation "As Administrator." To do this, right-click the RWIND Simulation icon and select "Run As Administrator."

      Figure 01 - Program Start

    2. Select the "RWIND Simulation - License and Authorization" function in the "Help" menu.

      Figure 02 - License and Authorization Settings

      This opens the "RWIND Simulation 1.xx Authorization Status" dialog box.

    3. Check in the "RWIND Simulation 1.xx Authorization Status" dialog box if an active software key authorization is available. This is the case if the "Software Key" option is selected in the "Authorization Method" section, and an active authorization is indicated by a green dot in the "Authorization Status" section.

      Figure 03 - Authorization Status

      If the check is negative, and a red dot is displayed, no RWIND Simulation license based on a software key is activated on the single-user computer. As a result, the activation period for a license cannot be extended.

      If the requirements mentioned above are met, click the "Extend Activation Online" button. The "Extend Activation Online" dialog box appears.

    4. The "Extend Activation Online" dialog box shows the license specification to be extended.

      Enter your online activation key based on your contract documents and define the new activation period in the date field.

      Then, click the "Extend Activation Now" function to run the online extension.

      Figure 04 - Extension of Activation

      This opens the "RWIND Simulation 1.xx" dialog box.

    5. In the "RWIND Simulation 1.xx" dialog with the confirmation prompt about the planned modification, click "OK" to finally change the activation period.

      Figure 05 - Confirmation Prompt

      After successfully changing the activation period, you receive a confirmation message and can use the program without restrictions.
    Thus, your purchased license is used in our system for the newly defined activation period. During this time, it is not possible to activate the RWIND Simulation program with the activation key on any other computer. The assignment of the license in our system ends with a proper deactivation or after the defined activation period has expired.

    To avoid unnecessary license assignments in our system due to unexpected computer problems on your part (defect, loss, hardware replacement, employee change, and so on), we recommend you to keep the activation period as short as possible.

  • Answer

    Potential window, door and facade openings can be included in RWIND Simulation by using the model simplification (shrink-wrapping mesh) for the wind flow analysis. This meshing option "refines" the imported models against the wind flow entering the model with the accompanying internal pressure load. To determine which opening should be closed and which openings should remain open, the program uses the size specification. Thus, all openings with the dimensions smaller than the specified control dimension will be closed generically for the wind flow analysis in the numerical wind tunnel.

    Figure 01 - Velocity Distribution for Closed and Open Building Structure

    In RWIND Simulation, you can specify the opening size in the "Edit Model" menu of the respective models.

    Figure 02 - Specifying Openings in RWIND Simulation

    The RFEM or RSTAB interface menu includes the opening size specification for the automatic calculation of wind loads in the background in the "Simulate and Generate Wind Loads" dialog box under the "Wind Load" tab.

    Figure 02 - Specifying Openings in RWIND Simulation

    In order to simulate a closed building structure, it is also possible to consider additional surfaces in the opening areas by using an STL import or directly using a load distribution surface in RFEM.

  • Answer

    During the development of the FRAME‑JOINT Pro add on module, the bottom end plate extension was introduced as it causes an improved load transfer of the compression force into the column.
    It is not possible to deactivate the extension and the minimum dimension of it is defined as follows:
    uu = max
    • End plate thickness
    • √2 * bottom flange weld
    • for end plate height < 200 mm → min 10 mm
    • for end plate height > 200 < 400 mm → min 20 mm
    • for end plate height > 400 → min 30 mm
  • Answer

    To correctly combine the planned prestress with the other load cases, define a suitable load case and apply a "pulling" strain load to the members concerned. The pulling strain load can be, for example:

    • a negative temperature load Tc distributed uniformly over a cross‑section,
    • a negative axial strain ε,
    • a negative axial displacement Δl,
    • a positive initial prestress V, or
    • a positive final prestress V (in RFEM only).

    The input by using the axial displacement is the most comprehensible input as you can directly measure the displacement at the turnbuckle of the tension member.

  • Answer

    Your network license is based on a NETSOFTLOCK. This license key will be activated on your server on a one-time basis.
    If you have received a new authorization file from us, it can be entered on the client's PC only. There are two possible scenarios:

    1. The authorization file is entered on a PC where there was no license used before. The activation menu appears. Now, please select the "Use Demo Version" option. Then, use the menu Help → Authorization → Import Authorization File to enter the new authorization file and then restart the program.

    2. The authorization file is imported on a PC where a license has already been used before.
    The program displays the warning about the invalid authorization. Then, you can run the program in DEMO mode. Now, use the menu Help → Authorization → Import Authorization File to enter the new authorization file and then restart the program.
  • Answer

    By default, the RSTAB 5 files with the .rst file extension are also opened with RSTAB 8. If you use other software that also works with the files that have the -rst file extension, you have to assign the default app for this file extension in the Windows settings. The procedure is shown in the video. This setting is preserved even after an update of RSTAB.
  • Answer

    This option is only available if there are nonlinear structural elements (for example, tension members) included in the structure. You can easily check if this is the case. Open the global calculation parameters and check in the "Nonlinearities" section at the bottom left whether the "Members due to member type" or "Member nonlinearities" option is available. If they are grayed out, there are no members with these parameters and the "Exceptional handling" option is thus unavailable, because there will be no failing members in such case.
  • Answer

    The corresponding file extensions of the respective programs are listed below:

    • .rf5 RFEM 5
    • .rf5t RFEM 5 Trial → Can also be opened in the full version on the same PC.
    • .rf4 RFEM 4
    • .rf3 RFEM 3
    • .rfe RFEM 2
    • .rfx RFEM → Table contents are saved in the XML format.

    • .rs8 RSTAB 8
    • .rs8t RSTAB 8 Trial → Can also be opened in the full version on the same PC.
    • .rs7 RSTAB 7
    • .rs6 RSTAB 6
    • .rst RSTAB 5
    • .rsx RSTAB 8 → Table contents are saved in the XML format.

    In addition to these file types specific to Dlubal Software, the program can create additional file formats. They are listed in Figure 01 (RFEM) and Figure 02 (RSTAB).
  • Answer

    If the load-bearing capacity of the wall surface is neglected and only applied to the ceiling as a load by using a line load, it would result in very large deformations.
    If the nonlinear property of the masonry is not considered, it would result in very small deformations.
    In principle, there are three options available in RFEM.
    • Line release: Vertical compression forces are only transferred. In this case, the nonlinear property is only applied for the force transmission directly to the connection line of both surfaces.
    • Nonlinear material "Isotropic Masonry": In this case, the tension stresses in the x- and y-direction (that is, vertical and horizontal) are reduced iteratively to the specified limit values by reducing the stiffness. Using this model, it is possible to represent the behavior of a masonry wall that is closest to reality, because the tension stresses are reduced in the direction of the mortar joints. This requires the RF‑MAT‑NL add-on module.
    • Nonlinear surface stiffness type "Membrane without tension": In this case, the tension stresses in the principal stress direction are reduced iteratively by reducing the stiffness.
  • 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

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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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