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  • Answer

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

    '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, here an example of a member:

    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 release hinge.

    For this purpose, the member end release must be created first, if not already available. Then, the IMemberHinge interface is brought to the member end release 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 release. 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, any possible modifications of the COM Interface are stated in our update report for the respective add-on module. All update reports are available on 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, complete compatibility is not 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, that is not possible. The report can not be opened or managed via the COM Interface. The only thing that can be done is to access the number of created reports in a list.

    It is possible to access the report templates. This is explained in the following FAQ. However, this can not be controlled by the COM Interface of RFEM/RSTAB, but by a general Windows functionality.
  • Answer

    Each module has its own method for calculating a case in a module. Here are the methods of the individual modules for the case calculation:

    RF-/Timber - IModuleCase -> Calculate()
    RF-/STEEL EC3 - ICase -> moCalculate()
    RF-/ALUMINUM - ICase -> moCalculate()
    RF-/STEEL - IstCase -> stResultsCalculate()
    RF STABILITY - IsbCase -> sbResultsCalculate()
    RF-/DYNAM Pro - IDynamModule -> Calculate()
    RF-/CONCRETE Members - IcoCase -> coResultsCalculate()
    RF-/CONCRETE Surfaces - IcoCase -> coResultsCalculate()

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