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  • Answer

    In order to only calculate specific load cases, load combinations, or result combinations in the same way as the "To Calculate..." command (see Figure 01), you can use the CalculateBatch method of the ICalculation interface. For the transfer, the method expects a field with the load type of Loading. This Loading includes the number of the load, and the type (for example, a load combination):

    Sub batch_test()
    '   get interface from the opened model and lock the licence/program
        Dim iModel As RFEM5.IModel3
        Set iModel = GetObject(, "RFEM5.Model")

    On Error GoTo e
        '   get interface for calculation
        Dim iCalc As ICalculation2
        Set iCalc = iModel.GetCalculation
        '   create array with loading types
        Dim loadings(3) As Loading
        loadings(0).no = 1
        loadings(0).Type = LoadCaseType
        loadings(1).no = 4
        loadings(1).Type = LoadCaseType
        loadings(2).no = 4
        loadings(2).Type = LoadCombinationType
        '   calculate all loadings from the array at once
        iCalc.CalculateBatch loadings

    e:  If Err.Number <> 0 Then MsgBox Err.description, , Err.Source
        Set iModelData = Nothing
        Set iModel = Nothing

    End Sub
  • Answer

    An imperfection is considered a load and is transferred via the interface of the load case. Provided that the interface to the model has already been imported, the interface to the loads (ILoads) followed by the interface to load case 1 (ILoadCase) will subsequently be imported, if it has already been created before:

            '   set loadcases
            Dim iLoads As iLoads
            Set iLoads = model.GetLoads
            '   get load case
            Dim iLc1 As ILoadCase
            Set iLc1 = iLoads.GetLoadCase(1, AtNo)
            '   define imperfection
            Dim imperf As Imperfection
            imperf.Comment = "test"
            imperf.Direction = LocalZType
            imperf.Inclination = 200
   = 1
            imperf.ObjectList = 1
            imperf.Precamber = 300
            imperf.PrecamberActivity = ActivityAccording_EN_1993_1_1
            '   set imperfection
            iLc1.SetImperfection imperf

    The data of the imperfection is then filled out first, here for member 1, and then transferred within a Prepare-/FinishModification block of the load case Interfaces.

  • Answer

    To modify an existing element, you have to get the interface to the corresponding element, shown here using a member as an example:

        Dim iModel As RSTAB8.model
        Set iModel = GetObject(, "RSTAB8.Model")
        Dim iModData As IModelData
        Set iModData = iModel.GetModelData
        Dim iMem As RSTAB8.IMember
        Set iMem = iModData.GetMember(1, AtNo)

    Use this code to get the interface to member 1, which must already be created. Then, you can use the .GetData () method of the interface to get the member data.

    If you want to modify data (such as the member rotation here), you can subsequently transfer it to the program within a Prepare-/FinishModification block with the method .SetData ().

        Dim mem As RSTAB8.Member
        mem = iMem.GetData
        mem.Rotation.Angle = 0.5
        mem.Rotation.Type = RSTAB8.Angle
        iMem.SetData mem
  • Answer

    The following code shows how to get different calculation parameters via the COM interface. It also demonstrates how to specify a setting for deactivating shear stiffness:

        '   get model interface
        Set iApp = iModel.GetApplication()
        '   get calculation interface
        Dim iCalc As RFEM5.ICalculation2
        Set iCalc = iModel.GetCalculation
        '   get surface bending theory
        Dim calc_bend As RFEM5.BendingTheoryType
        calc_bend = iCalc.GetBendingTheory
        '   get settings for nonlinearities
        Dim calc_nl As RFEM5.CalculationNonlinearities
        calc_nl = iCalc.GetNonlinearities
        '   get precision and tolerance settings
        Dim calc_prec As RFEM5.PrecisionAndTolerance
        calc_prec = iCalc.GetPrecisionAndTolerance
        '   get calculation settings
        Dim calc_sets As RFEM5.CalculationSettings
        calc_sets = iCalc.GetSettings
    'get calculate options
        Dim calc_opts As RFEM5.CalculationOptions
        calc_opts = iCalc.GetOptions
        '   set ShearStiffness to false
        calc_opts.ShearStiffness = False
        iCalc.SetOptions calc_opts

    In the annex, there is an EXCEL macro to download.
  • Answer

    Friction represents a non-linearity and can therefore only be modified via the interface to the member end hinge.

    For this purpose, the member end hinge must be created first, if not already available. Then, the IMemberHinge interface is brought to the member end hinge and then to the non-linearity (here IFriction). Then, you can use the methods GetData and SetData to modify the data (here Friction):

    Sub SetMemberHingeFriction ()

    Dim model As RFEM5.model
    Set model = GetObject (, 'RFEM5.Model')

    On Error GoTo e

    Dim data As IModelData
    Set data = model.GetModelData

    Dim hinge (0 To 0) As RFEM5.MemberHinge

        hinge(0).No = 1
        hinge(0).RotationalConstantX = 1
        hinge(0).RotationalConstantY = 2
        hinge(0).RotationalConstantZ = 3
        hinge(0).TranslationalConstantX = 4
        hinge(0).TranslationalConstantY = 5
        hinge(0).TranslationalConstantZ = 6
        hinge(0).Comment = "Member Hinge 1"
        hinge(0).TranslationalNonlinearityX = FrictionAType

        data.SetMemberHinges hinge
        ' get interface for member hinge
        Dim imemhing As IMemberHinge
        Set imemhing = data.GetMemberHinge(1, AtNo)
        ' get interface for nonlinearity 'friction'
        Dim iFric As IFriction
        Set iFric = imemhing.GetNonlinearity(AlongAxisX)
        ' get friction data
        Dim fric As Friction
        fric = iFric.GetData
        fric.Coefficient1 = 0.3
        ' set friction data
        iFric.SetData fric
    e:  If Err.Number <> 0 Then MsgBox Err.Description, , Err.Source

        Set data = Nothing
        Set model = Nothing

    End Sub

    In the case of the friction Vy + Vz, the Coefficient2 is used to set the second coefficient. The spring constant in the Friction dialog box is controlled by the translational spring of the member end hinge. In the concrete case, this is TranslationalConstantX for the X-direction (see Figure 01).

  • Answer

    The asynchronous calculation is used if a self-created program should only open or continue RFEM or RSTAB. When the calculation is complete, the event is transferred via a delegate. You can find a C# example in a Visual Studio project in the download area below.
  • Answer

    This check can be queried automatically via

    • "IApplication.LockLicense ()"
    • "bool isLicensed = IApplication.IsComLicensed ()"
    • "IApplication.UnlockLicense ()"

  • Answer

    To transfer several elements, you first have to create a field (array) in VBA:

    Dim nodes (0 to 2) as RFEM5.Node

    Then, you can transfer all nodes at once to the field (here three elements 0,1,2) with the method IModelData.SetNodes ().

    These methods are also available e.g. for the following structural elements:

    IModelData.SetLines ()
    IModelData.SetMembers ()
    IModelData.SetSurfaces ()
  • Answer

    Basically, possible modifications of the COM Interface are specified in our update report for the respective add-on module. All update reports are available under the following link.

    If there is a modification of the COM Interface, it is listed there. Especially when converting the older COM interfaces from RSTAB6/RFEM3 to RSTAB8/RFEM5, no complete compatibility is guaranteed due to the change from tlbs in the VBA to an integrated solution with dlls.

    However, it is usually possible to overwrite dlls within the current COM interface without any problems. For additional backups, it is always recommended to back up the old files.
  • Answer

    No, it is not possible. A printout report cannot be opened or managed via the COM interface. The only thing that is possible is to access the number of the created printout reports via a list.

    It is possible to access the report templates. This is explained in the following FAQ. However, this cannot be controlled by the COM interface of RFEM/RSTAB, but by the general Windows functionality.

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