Frequently Asked Questions (FAQ) - Search term: Result li...

The Calculation for Torsion in the NDS Strength Configuration works together with the torsion limit set to ensure the safety of the member and structure. Below, you find a short explanation for each option:

Check torsional limit only:
The ratio torsion check is compared to the torsion limit. If the ratio is smaller than the limit, then no further calculation is carried out. If the ratio is bigger than the torsion limit, an error will be shown in the design check. The error is then the most governing design check in the graphical and tabular results.

According to Timber Construction Manual:
Torsion design is according to the Timber Construction Manual 4.6, and the result is a typical design ratio based on the calculation.

Ignore torsion:
This setting is very similar to the first option. The ratio is compared from the torsion calculation to the torsion limit. If the ratio is smaller than the limit, then no further calculation is carried out. If the ratio is bigger than the limit, then a warning is shown in the design check. This warning will not be a governing design check in the results tables or graphics and serves only as a warning for safety considerations.

To neglect all torsion for the member design check, the limit value for torsion must be increased.

You can hide the undeformed geometry in the Display tab of the navigator by deactivating the Model check box:

The following programs and add-ons are particularly suitable for structural timber projects.

Main Program

To model your structure and determine the internal forces, you need one of the main programs. Depending on the application area, you can use RFEM 6 or RSTAB 9.

• RSTAB: Analysis of planar or spatial frame & truss structures
• RFEM: Finite element analysis of plate, wall, shell, and member structures

If your model has surface components, such as plates and walls, in addition to membe elements, you need RFEM. This program is the only one with the capability to analyze laminate or cross-laminated timber elements and curved objects.

Timber Design Add-on

Use the Timber Design add-on to design the timber components of your model. The design checks in compliance with specific standards cover both members (bending beams, columns) and surfaces (plates, walls). For columns, the stability analysis according to the equivalent member method or the second order analysis is performed.

You can perform the ultimate and serviceability limit state design checks, as well as the fire resistance design according to the following standards:

• EN 1995 – including National Annexes
• SIA 265
• NTC
• NDS
• CSA O86
• GB 50005
• AS 1720

In the fire resistance design, the charring of a cross-section is taken into account for both the stiffness and the design.

Multilayer Surfaces Add-On

With the Multilayer Surfaces add-on for RFEM, you can analyze laminate and sandwich structures with user-defined layer structures. This allows you to design cross-laminated timber panels, for example.

If certain layers have nonlinear material behavior, you can assign the appropriate properties to them. Furthermore, this add-on allows provides you with the option to analyze curved surfaces.

Additional Add-ons

In case of special requirements for your timber structure, we recommend further add-ons and additional programs to help you solve the task.

If you need to perform seismic or vibration analysis, the dynamic analysis add-ons provide you with powerful tools for your structural analysis and design. The Modal Analysis add-on enables the calculation of natural frequencies, and in combination with the Response Spectrum Analysis add-on, you can also perform seismic analysis according to numerous standards.

If you are designing a building with a complicated shape, so that the determination of wind loads according to the relevant standards reaches its limits, the RWIND RWIND program will help you: Using a CFD analysis, you can determine the wind loads even for highly complex building shapes.

If the construction stages affect the final internal forces in a structure, or if the governing internal forces for the structural design result from certain construction stages, you should consider the modeling using the Construction Stages Analysis add-on. The Building Model add-on allows you to easily enter large multi-story timber structures.

Please note that the enveloping results are usually shown when displaying the results of design situations or result combinations.

There are three options to graphically display the results of deformations, internal forces, and support forces: Max and Min-values can be displayed separately. To display both envelopes from the extreme values on the model, select Max and Min-values.

If a Rhino surface cannot be created by using the geometry type, it will not be transferred. This is the case, for example, of curved surfaces with more than four boundary lines. In the Rhino command history (_CommandHistory or the F2 key combination), you can find a list of warnings and errors displayed during the transfer process:

The CFD simulation (Computational Fluid Dynamics) is a valuable tool for various areas of engineering, design and research. In the following, we present some of the most important advantages of CFD simulations in more detail.

Cost Efficiency

Using CFD simulations in large or complex structural systems is much more cost-effective than performing physical experiments. For example, the digital wind simulation eliminates the costs for the production of prototypes, securing test facilities, and the use of special equipment

Saving Time with CFD Simulations

You can also save some time in the analysis process by using a CFD simulation. The setup and execution are quick and easy, requiring only a few clicks, which saves you a lot of time compared to setting up a physical test. As an engineer, you can thus benefit from iterative analysis processes. Test your designs in a virtual environment to perfect all aspects digitally before deciding on a physical prototype.

Detailed Visualization

For example, CFD provides you with flow patterns, pressure distributions, and other relevant physical phenomena that would be difficult or impossible to demonstrate experimentally. This additional information gives you an even better insight into the technical data of your project.

Scalability in CFD Simulations

Another advantage of the CFD simulations is the arbitrary scalability without great effort. Do you want to analyze different sizes or configurations of an analysis? In the digital flow tunnel, this is easily possible without any physical changes or new prototypes. A CFD simulation provides you with a wider range of scenarios and analysis parameters.

Sustainability Due to CFD Simulations

Another benefit of the CFD simulation is that it requires fewer physical prototypes and experiments. Lower energy consumption and lower waste production is ideal for achieving sustainability goals, such as reduced material costs and addressing environmental concerns.

Complexity and Precision

A digital wind tunnel gives you the opportunity to accurately model complex geometries and fluid interactions. This would be difficult to replicate in an experimental setup. The precision of CFD allows you to analyze subtle effects and interactions in a controlled environment. At the same time, the program provides you with complex insights that enhance the comprehension and optimization of structural systems.

The CFD simulations are especially useful if you have a thorough comprehension of the underlying models and assumptions. In most cases, it is best to use a combination of CFD simulations and experimental tests to achieve comprehensive results. This gives you the opportunity to fully understand the behavior of your structures in flow situations.

Are you looking for a way to carry out CFD simulations for your projects? The powerful RWIND is a stand-alone program that allows you to perform flow simulations in various situations. Find more information about the latest program generation here: RWIND 2 .

The following programs and add-ons are perfectly suitable for your reinforced concrete projects.

Main Program

To model your structure and determine the internal forces, you need one of the main programs. Depending on the application area, you can use RFEM 6 or RSTAB 9.

• RSTAB: Analysis of planar or spatial frame & truss structures
• RFEM: Finite element analysis of plate, wall, shell, and member structures

If your model has surface components, such as plates and walls, in addition to membe elements, you need RFEM.

Concrete Design Add-on

Use the Concrete Design add-on to design the reinforced concrete components of your model. The design checks according to specific standard include not only members (bending beams, columns) and surfaces (plates, walls), but also surfaces susceptible to punching shear. For columns, the stability analysis according to the nominal curvature method is integrated in the add-on.

You can specify user-defined reinforcement or determine it by using the program. With these basic conditions, you can perform the ultimate and serviceability limit state design checks according to one of the following standards:

• EN 1992, including National Annexes
• ACI 318
• CSA A23.3
• SP 63.13330

The add-on also allows for deformation analyses for cracked reinforced concrete surfaces (state II) using the approximation methods described in the standards. Tension stiffening as well as creep and shrinkage can be taken into account.

Additional Add-ons

If you have special requirements for the reinforced concrete structure, we recommend further add-ons and additional programs to help you solve the task.

To use a cross-section that is not included in the extensive cross-section library of RFEM 6 or RSTAB 9, the RSECTION program helps you when modeling the cross-section including reinforcement. You can then design this cross-section as usual in the Concrete Design add-on.

If you need to perform seismic or vibration analysis, the dynamic analysis add-ons provide you with powerful tools for your structural analysis and design. The Modal Analysis add-on enables the calculation of natural frequencies, and in combination with the Response Spectrum Analysis add-on, you can also perform seismic analysis according to numerous standards.

If you are designing a building with a complicated shape, so that the determination of wind loads according to the relevant standards reaches its limits, the RWIND RWIND program will help you: Using a CFD analysis, you can determine the wind loads even for highly complex building shapes.

If the construction stages affect the final internal forces in a structure, or if the governing internal forces for the structural design result from certain construction stages, you should consider the modeling using the Construction Stages Analysis add-on. The Building Model add-on allows you to easily enter large multi-story concrete structures.

Basic Add-ons

If you design steel structures, you need the following add-ons in addition to RFEM or RSTAB:

• Steel Design
• Stress-Strain Analysis
• Stability
• Steel Joints

The Steel Design add-on allows you to perform stability analysis (lateral-torsional and torsional-flexural buckling) in addition to the normal cross-section design.

The Stress-Strain Analysis add-on calculates not only stresses, but also strains in members, surfaces, and solids.

Steel structures are usually slender structures so the stability plays an important role. Use Structure Stability add-on to calculate the effective lengths and critical load factors for a precise stability analysis.

Model the connections between members precisely and flexibly using the Steel Joints add-on that is based on FEA. The connections need to be loaded not only in the main load-bearing plane. Even if the connection is loaded about the "minor axis", you can dimension the connection using this add-on.

Additional Add-ons

If you have special requirements for steel design checks, there are other add-ons and additional programs available to support you in solving your special tasks.

To use a cross-section that is not included in the extensive cross-section library of RFEM 6 or RSTAB 9, the RSECTION program helps you when modeling the cross-section and calculating the section properties.

If you want to analyze the lateral-torsional buckling with the more accurate and cost-effective method with 7 degrees of freedom, you will need the Torsional Warping (7 DOF) add-on.

If it is necessary to consider the plastification of the material when determining the internal forces, you can use Nonlinear Material Behavior add-on.

The Modal Analysis add-on enables the calculation of natural frequencies, and in combination with the Response Spectrum Analysis add-on, you can also perform seismic analysis according to numerous standards.

If you are designing a building with a complicated shape, so that the wind load calculation according to the relevant standards reaches its limits, then the RWIND program will help you: Using a CFD analysis, it can determine wind loads even for the most complicated building shapes.

If the construction stages affect the final internal forces in a structure, or if the governing internal forces for the structural design result from certain construction stages, you can model this using the Construction Stages Analysis add-on.

The Building Model add-on allows you to easily enter large multi-story concrete structures.

For your design of lightweight steel structures, containing cables and membranes, the Form-Finding add-on can help you to determine the shape of the structure.

A reason for the calculation time taking a while with little utilization of your computer's processor can be caused by using the Iterative instead of the Direct solver. Both options control the method used for solving the equation system.

The direct solver is a method that uses matrix decomposition techniques, such as the LU decomposition, to solve the system of equations in a single step. This approach is generally more robust and can handle any type of problem, but it may require more memory and computational resources, especially for very large systems.
The iterative solver, such as the Conjugate Gradient method or the GMRES (Generalized Minimal Residual) method, solves the system of equations by iteratively refining the solution.

The solver method that leads to the quicker results depends on the complexity of the model as well as the size of the available main memory amount of RAM in the machine. If resources are not a concern when solving large complex models, then the Direct solver is recommended for a majority of the time and will be the quickest. Make sure to check this under the Static Analysis Settings within RFEM 6.

The "Beam Panel" element will allow you to model entire buildings or only certain areas with using surfaces for timber shear wall panels.
By introducing the necessary line hinges in the rigid couplings, the "Beam Panel" element was also released, which will now be further optimized step-by-step in order to achieve the goal mentioned above.
Currently, the application is limited to very simple structures. However, we are very focused on improving the application as quickly as possible. The current state of development is summarized in this FAQ:

Current State and Planned Development:

• Modeling of single, independent surfaces
• Boundary lines orthogonal to each other and not interrupted (four boundary lines, except across surface cells)
• Openings possible via surface cells
• Automatic connection stiffness calculation according to EN 1995‑1‑1 (linear) for nails and fasteners
• More convenient input and extension for all standards (in development)
• Rotation orthotropy direction of sheathing (in development)
• Semi-rigid coupling of adjacent elements (in development)
• Different cross-sections for boundary members in the positive and negative directions (in development)
• Optional no definition of boundary members (in development)
• Connections of panel joints (corners, T-joint, wall-slab) (in development)
• Integration of modeling tools (drag and drop, copy...) (in development)

The Structure Stability add-on is not dependent on the settings made in the Steel Design add-on. It is a global stability analysis of the entire structure according to how the model is created. The setting of boundary conditions is only used for the design in the Steel Design add-on.
If you want the top flange to be supported, for example, we recommend using objects from Types for Members → Member Supports → Shear Panel. These objects are reflected in the results of the add-ons for dynamic and stability analysis.
In order to take into account the shear panel, it is necessary to activate this option of structural modification for the selected load cases or load combinations.

No, it is not possible to deactivate the Mia assistant. However, if the avatar is in a distracting position, you can simply move it by using the mouse.

Our AI assistant is continuously being developed. In the future, Mia will become much more integrated in RFEM and it is learning new things every day. Our goal is to make your work with RFEM even more intuitive and easier.

Mia provides you with the opportunity to use the capabilities of large language models (LLM) for the structural analysis and program operation of RFEM 6 and RSTAB 9.

Mia already offers a number of advantages:

Support 24/7, including weekends

Perhaps you know this situation, too: a project that still needs to be finished. Shortly before the end, problems arise for which you urgently need support, and the phone support has already closed.

Mia can help you to find a solution to your problem in this situation.

Better work efficiency

You will get the answers to your problems directly. You don't need to interrupt your work until the support has responded to your question.

Communication in almost any language

Mia has an integrated translation function. Communicate in the language that is easiest for you.

Easy access to information

You don't need to search through long articles to finally get the information you are looking for. Instead, you get exactly the information that is relevant to your question.

Easy to use

Simply describe your problem in natural language. It's no longer necessary to formulate complicated Google search queries and to search in countless documents for the results.

User friendliness

The AI function of Mia is directly integrated into the program interface of RFEM 6 and RSTAB 9; that is, exactly where the questions arise. It is no longer necessary to switch to the browser and open a specific website.

Free access

With Mia, you get free, fast access to the support team.

In the shortcut menu, you can find some important functions that support you when working with RFEM 6 and RSTAB 9.

Test Mia yourself. The answers are not always perfect, but are often amazingly good and effective. By the way, Mia also has a sense of humor.

More Information About Mia:

First, it is worth taking a look at the "Load Transfer" tab when editing the surface. If the load transfer direction is set to "Isotropic | FEM", the loads are not displayed until the load case or load combination has been calculated, as they must be calculated in a sub-model first. So make sure the results are available there.

The most important functions for using RFEM are described in the online manual. It also includes a short theoretical chapter on finite elements. Useful information about modeling and result evaluation for calculations according to the Finite Element Method can also be found in the technical articles of our Knowledge Base.

Of course, the documentation cannot replace the technical literature. To help you get started with finite elements, here are some recommended readings:

• Barth, Christian, & Rustler, Walter. (2013). Finite Elemente in der Baustatik-Praxis. (2nd ed.). Bauwerk. (➥ Amazon)
• Werkle, Horst. (2021). Finite Elemente in der Baustatik. (4th ed.). Springer Vieweg. (➥ Amazon)
• Nasdala, Lutz. (2015). FEM-Formelsammlung für Statik und Dynamik. (3rd ed.). Springer Vieweg. (➥ Amazon)
• Němec, Ivan. (2010). Finite Element Analysis of Structures – Principles and Praxis. Shaker-Verlag. (➥ Amazon)
• De Souza Neto, Eduardo A. (2008). Computational Methods for Plasticity – Theory and Applications. Wiley. (➥ Amazon)
• Rombach, Günter. (2000). Anwendung der finiten Elemente im Betonbau. Ernst & Sohn. (➥ Amazon)

This list is only a small selection of the recommendations. You can also find further technical literature in the references of the mentioned works.

Accuracy of RWIND Results and Ratio of Accuracy Versus Cost

The RWIND program was designed to quickly and easily calculate wind flow around buildings in order to obtain pressure values on their surfaces and generate load forces. In order to meet this main goal, a number of compromises had to be made, such as allowing the use of a simplified model or a relatively coarse computational mesh. It is obvious that these simplifications affect the accuracy of the results. Increasing the accuracy of the results using a finer mesh and other user settings in RWIND is possible, but this process may not be easy and requires sufficient experience with CFD simulations. An important question here is what is the acceptable ratio of effort and cost to the improvement in accuracy achieved. We recommend reading the CFD Project Accuracy vs. Effort article which deals with this issue in detail.

RWIND Error E315

When increasing the mesh density, memory and performance requirements do not grow linearly, but with the 3^rd to 4^th power (we have three spatial dimensions and also a reduction of the time step is necessary). This not only leads to a significant slowdown of the calculation, but also various problems can start to appear, which are usually related to the fact that the program approaches its limits or the limits of the hardware used. These problems also include error E315 which indicates a general failure inside the OpenFOAM© calculation modules – such as memory allocation failure, loss of numerical precision, and so on. The specific reasons for the failure can be different. More detailed information can be found from the relevant Log File.

RWIND Customer Support and its Limits

Dlubal customer support always tries to help RWIND users who encounter any problems. However, numerical simulations of wind flow can be very complex and results cannot generally be guaranteed. This is due to the fact that there is still no mathematical proof of the existence and uniqueness of the solution of the Navier-Stokes equations that describe this flow and which RWIND solves numerically using the finite volume method. Although the calculation converges to the correct solution in most cases, a failure of the calculation cannot be excluded. In the event that a calculation failure occurs in a large and complex project, assistance can be very time-consuming. If you are interested in additional extended assistance, please Contact Our Sales Team.

Regular expressions allow you to convert several objects, such as an entire IPE section series, by a single entry.

Example

Conversion of, for example, IPE120 in Tekla to IPE 120 | Euronorm 19-57; ... | SZS in RFEM 6 should also work for all other cross-sections of the IPE cross-section series.

In order to create a conversion for the entire IPE cross-section series, the regular expression is structured as follows:

For the expression (\d+), you can enter any decimal number. (IPE200, IPE300,...)

The expression $1 refers to the entered decimal number. In the following image, the regular expression has been added to the Tekla conversion table.

If two decimal numbers are used, the expression $1 refers to the first number and $2 refers to the second number. The following table shows this, using the example of the material conversion.

This article shows and explains possible problems when defining regular expressions.

The cross-section name 400*400 is not converted with the expression (\d+)*(\d+).

The asterisk * has a special meaning in regular expressions, and is therefore not interpreted as a simple character. To use the asterisk as a single character in a regular expression, you can write it with a backslash \ to invalidate its special meaning.

The cross-section name RHS200*100*5 is not converted with the expression RHS(\d+)\*(\d+)\*(\d+).

If several similar regular expressions are used, this may result in the use of an incorrect regular expression (see the example in the image).

You can use the superscript ^ to specify using a regular expression only if it is valid at the beginning of the material or cross-section name. The expression ^(\d+)\*(\d+) is thus no longer valid for the RHS section, because this section name does not start with a number (such as 400x400).

How can I convert the material/cross-section from RFEM 6 regardless of the standard designation?

In contrast to RFEM 6, Revit and Tekla assign material and cross-section names regardless of the standards. Therefore, to convert, for example, an HEA 300 cross-section in RFEM 6 into an HEA 300 with no standard reference in Revit or Tekla, you can use the regular expression .*$ to ignore the standard designation in the name.

The programs RFEM 6 and RSTAB 9 are connected to a personal Dlubal account. This also applies to the viewer or demo mode. To ensure that your partner can create a new account, all they need to do is to enter their email address and password.

After starting the trial or demo version and logging in, your partner can open the model. The usual view functions are available for viewing objects. However, the model cannot be edited, calculated, or saved.

Results can only be viewed in the same program version as the model was saved in!

In order to evaluate user-defined points in addition to the result values on grid points and FE mesh nodes, there is the option to specify "Additional Surface Result Points" in RFEM 6. You can find them under "Types for Surfaces", as shown in Image 01.

The coordinates for these points are entered directly in the dialog box or selected in the model; see Image 02. Furthermore, it is necessary to assign the surface whose result values should be displayed.

In the Results navigator (the upper half), you can activate and deactivate the display of the manually specified result values. In the lower half of the Results navigator, you can set the display for grid points and/or surface result points; see Image 03.

When displaying the values in FE mesh points, the additional surface result points are deactivated.

To avoid punching reinforcement, it may help to apply additional reinforcement in some areas. If the existing reinforcement in the punching shear area does not increase despite the reinforcement, the following problem is the cause:

• The additional reinforcement requires the minimum dimensions or a required reinforcement length to be applied for the calculation.

It is calculated according to Section 6.4.4 / Equation 6.47 of EN 1992‑1‑1. In the example, this is shown for a rectangular column.
The basic reinforcement is 3.35 cm²/m, the additional reinforcement is also 3.35 cm²/m. If both reinforcements are effective, the result is a reinforcement of 6.7 cm²/m.

• The program does not consider the required anchorage length of the additional reinforcement. It is necessary to adjust it manually.

• In order to illustrate the problem, we calculate with a very fine mesh in the example. The required dimensions when entering additional reinforcements may increase if a very coarse mesh is set. Therefore, the required minimum length can then jump to the next mesh element here.

The Earthquake Limit State (with and without overstrength) only provides a result for members with an assigned Seismic Configuration.
The Strength Limit State is used to design all members, including the members that are not part of the seismic force-resisting system (SFRS). Therefore, both Earthquake and Strength Limit States are required.
The Serviceability Limit State is also available.

Image 01 is an example of the required design situations for the LRFD Design.

Notes:
1) The web ductility check per Table D1.1 of AISC 341‑16 (RFEM EQ 1100) is applicable to all load combinations, including non-seismic COs. Therefore, the Earthquake Limit State is also applied to Equations 1 to 5 (Design Situation DS5 in Image 01).

2) For the Combination Wizard, the “Result Combinations” is required when using the response spectrum analysis.

Yes, it is.
To deactivate the blue/red colors in the result tables, click the "View" menu of the tables, and press the "Display Color Scale" button. You can also use the corresponding button in the table toolbar.

For the printout report, you can also deactivate the "Color Scale" option in the "Printer and Page Settings" dialog box in the "Other Settings" tab.

If this error message appears, RFEM/RSTAB cannot connect to the server managing the cloud calculations.

Please ask your IT department to check the communication with our server. It is necessary to enable the following access in the firewall policies as well as in the network:

• Server name: cloud.dlubal.com
• Server IP: 89.187.130.211
• Server Port: 443

If the connection still does not work after this procedure, your IT department needs to check whether the SSL certificate has been exchanged, based on your internal guidelines (for example, using a proxy). They should be able to check this with software (for example, OpenSSL) in the command line:

• cd C:\Program Files\OpenSSL-Win64\bin
• openssl.exe s_client -connect cloud.dlubal.com:443

In the Load Combinations tab, select the load combinations (COs) to be excluded and then uncheck the "To Solve" option (Image 01).

Alternatively, the COs or RCs (result combinations) can be excluded in the table of the design add-on (Image 02).

Compression elements in members subjected to pure axial compression can be designed according to CSA S16. For members subjected to flexure or combined loading (flexure + compression), the design is currently not possible.

For a member with a very small flexural load, the load can be ignored by increasing the limit in the Ultimate Configurations to avoid the 'non-designable' result.

As of the version 6.03 (RFEM) and 2.03 (RWIND), the results calculated in RWIND can also be displayed in RFEM.

To do this, you just need to activate the "Wind Simulation" add-on in RWIND and start the corresponding calculation.
RWIND appears and performs the simulation. Once the calculation has been completed, the following dialog box appears.

By clicking "Yes", RWIND is closed and RFEM loads the result data. In the result display in RFEM, you can now display the properties related to the surface, as shown in the following image. You can use the navigator in the top left to switch between the results of the structural analysis and the wind simulation.

Corrugated web beams allow for further optimization of steel structures. They are often used to reduce the self-weight of main load-bearing elements and to prevent buckling failure of webs due to the corrugation.

This example will be based on a WTA – 1250 – 300x20 Beam from the Zeman catalogue.

To create a model of this beam, it's best to start by modeling a sine wave that will be used to edit the web. This consists of the steps shown below and in the attached images.

• Create nodes representing sine function
• Copy nodes to desired length of beam
• In RFEM's Lines table, manually create spline from 1st to last node

After these steps, it's recommended to create a parametric section with the dimensions of the corrugated beam. Members using this section can later be transformed into surfaces.

• Create a parametric section with the geometry based on desired beam
• Generate surfaces from members

With this set of surfaces, it is recommended to copy the sine spline into the position of the top and bottom edge of the surface representing the web.
Later, it is required to change the geometry type of the web surface to Quadrangle and redefine the boundary lines of this element.

• Copy sine into top and bottom of web
• Change web geometry type to Quadrangle
• Exclude straight lines from web surface and add sine lines

After preparing the geometry, it's required to focus on finishing the model for the calculation. Select the start and end lines of the member and create a member with the type Rigid. After that, it's possible to define nodal supports on the beam and loads in the model. In order to check the resulting internal forces of a member, it is recommended to define a result beam on the main center line. Finishing all of these steps allows us to start the analysis of the beam.

• Define rigid members on external lines of surfaces
• Add nodal supports
• Add loads – use line loads, not member loads for continuous loading
• Define a result beam on the center line
• Perform the analysis

Remember to define proper mesh settings with an adequate target length of the finite elements and to use a line mesh refinement on the sine lines.

Combinations can be modified, of course. It is necessary to turn off the automatic generation of combinations in the Base Data of the model, but keep the previously created combinations.
Then, add a new load case to the combination in the "Edit Load Cases and Combinations" dialog box.
In the final design checks, the change takes effect after the recalculation.

The display of internal forces for couplings (coupling members, rigid members) is deactivated by default in RFEM 6 / RSTAB 9. However, you can quickly enable the display of internal forces and deformations for these member types under the Navigator - Results - Members options by selecting the "Results on Couplings" checkbox.

Requirements

In order to transfer support forces from other models, two conditions need to be met:

1. The load wizard "Import Support Reactions" is available as of the program version X.02.0071 (or later).
2. Both models must be in the same project (the same project ID). It is necessary to reconnect the existing projects in the Dlubal Center, if necessary.
3. Both models must have different model IDs.
4. In the model where the loads are to be applied (hereinafter referred to as a "child" model), load cases need to be created.

To ensure that the models have different IDs, it is necessary to create each model via "File → New...". As an alternative, you can also save the existing model as a copy via "File → Save As..."; thus, it obtains a different ID. You can view the IDs under the model parameters in the Base data of a model.

Procedure

If the requirements are met, you can select the "Import Support Reaction" load wizard in the "child" model and assign the "parent" model there in the Model tab (Image 01).

In the Objects tab, the assigned lines and nodes of the "parent" model are assigned to the lines and nodes to be loaded in the "child" model (Image 02).

Assigning Nodes and Lines

It is important to note that the nodes and lines are assigned using their numbering. Pay attention to the order of the entry and the orientation of the lines.

Finally, you can select the assignment of the load cases and the load directions to be imported in the Load tab. Image 03 shows a pure transfer of the vertical loads in Load Cases 1-3.

As soon as you confirm the load wizard, the applied loads appear with the value "??" first. The correct value is only displayed once the respective load case has been calculated (Image 04). This calculation also triggers the calculation in the "parent" model.

Changes in Related Model

If there are changes made in the "parent" model, the load in the "child" model is reverted to "??", provided that the "parent" model has been saved. A recalculation of the load case in the "child" model transfers the new values.

The problem is that the load does not act in the specified direction but around the specified direction. If the resulting deformation is to be in the vertical direction, the load is entered around the y-axis. As soon as you do that, the resulting deformation shows the precamber.