The Nonlinear Material Behavior add-on enables the consideration of material nonlinearities in RFEM 6. This article provides an overview of the available nonlinear material models, which are available after activating the add-on in the model’s Base Data.
The Construction Stages Analysis (CSA) add-on allows for the design of member, surface, and solid structures in RFEM 6 considering the specific construction stages associated with the construction process. This is important since buildings are not constructed all at once, but by gradually combining individual structural parts. The single steps in which structural elements, as well as loads, are added to the building are called construction stages, whereas the process itself is called a construction process.
Thus, the final state of the structure is available upon completion of the construction process; that is, all the construction stages. For some structures, the influence of the construction process (that is, all the individual construction stages) might be significant and it should be considered so that errors in the calculation are avoided. A general overview of the CSA add-on is given in the Knowledge Base article titled “Consideration of Construction Stages in RFEM 6”.
If you want to consider guide objects in the overall view (F8 key or double-click on the mouse wheel) or, for example, in a particular direction of the views, you can enable this option in the settings of the particular guide objects (guidelines, background layers, line grids).
In RF‑TENDON and RF‑TENDON Design, you can review and adjust the code‑dependent factors, calculation parameters, and calculation methods using the "Code" button. You can display the settings and adjustment options according to a chapter of a code, selecting the "Grouping" option in the dialog box.
RFEM and RSTAB save the input data, the FE mesh, the results, the printout reports, and the 3D gITF model preview, including all visual objects, in one file.
RFEM and RSTAB offer many display options in the Display Navigator. They can be completely different, depending on their function. You often have to click several times to make certain changes. If you want to optimize your work, you can create user‑defined views. In these views, you can save all specified settings. The following example illustrates this principle.
When designing several members in one design case, it is sometimes difficult to recognize the governing design checks. To improve the overview and to display the relevant design checks in a compact way, you can use the filter options under the result tables. These are included in all design modules of steel, aluminum, and timber structures in RFEM and RSTAB.
In RFEM 5 and RSTAB 8, you can save problems and warnings occurring during the model check as an extra view. This way, you can easily work through the hints and messages, one after the other, cleaning the model. The function is available for double nodes, overlapping members/lines, and surfaces.
The RF‑/JOINTS add‑on modules are equipped with a graphical window that shows all the structural components of the connection. There, you can use the mouse functions known from RFEM and RSTAB to zoom, move, or rotate the view.
For a quick overview of the cross‑sections used, you can show the members in color sorted by cross‑section. Use the right mouse button in the work window to select "Colors in Graphics According to" → "Cross -Sections" from the shortcut menu. In the current program versions, you can use a panel with an editable color scale for this.
The transparency intensity of various graphic elements in the Solid Transparent Display Mode can be edited individually in the Program Options dialog box under the Graphic tab to improve the overview.
You can assign comments to each element in RFEM and RSTAB (structure element, load element, and so on). This can help to improve the overview and documentation of structures, as the comments appear in the printout report and, for example, certain objects can be filtered and displayed using the "Select Special" function.
The ISM file (ISM = Integrated Structural Modeling) in RFEM and RSTAB provides an interesting option for exchanging data. If you export a model to this data format, you can view and analyze it with the free ISM viewer from Bentley.
In RFEM 5 and RSTAB 8, you can view detailed information on the currently used license and installed dongle driver. In case of any problems with the license, you can send the created text file to the Dlubal Software hotline, which allows us to provide you with a fast and efficient analysis. To create the file, select "Help" → "Authorization" → "Diagnostics".
RFEM 5 allows you to use many different member nonlinearities for designing a model. In the following text, we look at an example of the use of the "slippage" member nonlinearity. The example is a simplified model of a concrete manhole with a square plan view.
The description of load cases, load combinations, or result combinations is often longer than fits into the drop‑down combo box "Current Load Case, Load Combination, Result Combination or Module Case" in the toolbar of RFEM or RSTAB.
When determining the minimum reinforcement for the serviceability limit state according to 7.3.2, the applied effective tensile strength fct,eff has a significant influence on the determined amount of reinforcement. The following article gives an overview about determining the effective tensile strength fct,eff and the input options in RF-CONCRETE.
The Project Manager is installed by default when installing RFEM and RSTAB and it manages all projects and calculation files. In the Project Manager, you can link different projects to have a clear overview of the program files.
Different methods are available for calculating the deformation in the cracked state. RFEM provides an analytical method according to DIN EN 1992-1-1 7.4.3 and a physical-nonlinear analysis. Both methods have different features and can be more or less suitable depending on the circumstances. This article will give an overview of the two calculation methods.
RFEM offers different options for the graphical display of results that have been determined in RF-CONCRETE Surfaces. This article gives an overview of these options.
After running an analysis in RF-/STEEL AISC, the mode shapes for sets of members can be viewed graphically in a separate window. Select the relevant set of members in the result window and click the [Mode Shapes] button.
In the BIM workflow, IFC files are frequently used as the basis for data exchange between CAD and structural engineering software. However, there is a fundamental problem with this approach. This article explains various types of IFC files and provides an overview of the import and export options in Dlubal Software programs.
In RFEM, structures can be modeled and analyzed in a spatial environment. The permanent 3D visualization helps you to better understand complex models and to represent the force flux. However, you can switch from a spatial mode to a planar sheet mode in the documentation of a calculation. To do this, you have to describe the spatial calculation of the structure with all the necessary properties on "flat" paper pages for an independent reader. Usually, you try to display the load actions and the corresponding results by using an orthogonal view of the substructure of the entire structure. Obviously, the load symbols depicted in the 3D mode in a view perpendicular to the load become unrecognizable due the missing expansion. In order to be still able to create a clear representation of all information, the corresponding adjustments are available in RFEM.
For the serviceability limit state design according to Section 6.6 of Eurocode EN 1997‑1, settlement has to be calculated for spread foundations. RF-/FOUNDATION Pro allows you to perform the settlement calculation for a single foundation. For this, you can chose between an elastic and a solid foundation. By defining a soil profile, it is possible to consider several soil layers under the foundation base. The results of the settlement, foundation tilting, and vertical soil contact stress distribution are displayed graphically and in tables to provide a quick and clear overview of the calculation performed. In addition to the design of the foundation settlement in RF-/FOUNDATION Pro, the structural analysis determines the representative spring constants for the support and can be exported to the structural model of RFEM or RSTAB.
Click the [Details] button in RF-GLASS to select the results to be displayed. In order to get a better overview for the result evaluation, you can select the individual stress graphics (principal stresses, stresses oriented to axes, shear stresses) as well as various result windows. This way, you can show only the results you require.
As in RFEM, load combinations can be generated automatically in RF‑PIPING. This feature is activated by default and creates the recommended load and result combinations for piping design. It is necessary to assign the relevant action category to load cases in order to generate the correct combinations. To do this, new action categories have been implemented specifically for loads on piping. Pressure temperature conditions are generated as the sets of the first (second, third, and so on) load case of the "Pressure" category and the first (second, third, and so on) load case of the "Temperature" category. The default setting can be reviewed or adjusted in the "Grouping of Thermal and Internal Pressure Load Cases for Operating Combinations" dialog box. You can access this dialog box by clicking the corresponding button in the "Piping Load Combinations" tab of the "Load Cases and Combinations" dialog box. This dialog box is automatically offered to check your entries in the case of any change of the load case from the "Pressure" or "Temperature" category.
The DXF interface in RFEM now exports a 3DFACE element in the DXF file for each FE mesh cell of the exported structure. The 3DFACE element is detected by AutoCAD during import, for example, and can be displayed as a surface in the graphic. Different visual styles help display the 3DFACE surfaces in a desired view.