As requested by many customers, the nodes are now represented by cubes after export using the direct interface to AutoCAD or in a DXF file. If you want to reuse the AutoCAD data in RFEM or RSTAB, make sure not to import all the layers when specifying the settings for the import.
During the cooperation between the structural and design engineers, the DXF format is often used if there is no direct interface. However, the geometrical data of these DXF files are not always accurate. For example, an inaccuracy in the third decimal place is not noticeable, but it can lead to numerical problems when generating the FE mesh in RFEM.
The interface between RFEM/RSTAB and Autodesk Revit has been improved: You can now transfer results from RFEM/RSTAB to Revit and display them there graphically. This option is available in a new tab when importing a file.
In RFEM, there are a file‑based and a direct DXF interface. The file-based DXF interface allows you to export the data in a DXF file that is transferred directly into an open AutoCAD file. In the interface dialog box, you can select which data are to be exported (results as isolines, result values, or finite element mesh with boundary and integration lines).
RFEM and RSTAB provide numerous interfaces with other programs for data exchange. In the respective programs, different names are often used for the same materials and cross-sections. Therefore, it is necessary to convert the material and cross‑section names in order for them to be recognized by the program after the data exchange.
The national parameters of EN 1992‑1‑1 for each country can be exported from RF‑/CONCRETE, RF‑/CONCRETE Columns, and RF‑/FOUNDATION Pro. To do this, there are interfaces with MS Excel, OpenOffice, and CSV. By exporting the national parameters, you can edit them in (for example) MS Excel, and display possible differences between the individual National Annexes clearly (see the image).
The RFEM or RSTAB user interface can be customized. The previous posts describe how to create toolbars and menu bars. Thus, this post focuses on the load case drop‑down list. This drop‑down list allows you to switch between individual load cases, combinations, and module cases.
RFEM and RSTAB provide the export interface ("File" → "Export") to export model and load data, as well as results, to Excel or in a CSV file in one step. You can select the tables to be exported in the "Export Tables" section. The "Only selected tables" option allows you to export only a specific selection of tables. Use the [Select Load Cases and Tables for Export] button to open the corresponding dialog box.
In RFEM and RSTAB, several interfaces are available. The DSTV interface (*.stp) is the most convenient for importing beam structures, since supports, hinges, loads, and load combinations are also transferred, in addition to the general topology.
In his bachelor's thesis, Jonas Mösch analyzes the open and closed interfaces in BIM-based structural design. The theoretical section covers the definition of the term "Building Information Modeling".
The first part of the post about the COM interface describes opening and closing RFEM. VBA programming language is used in Excel; however, the program sequence is the same as for programming with C#. First, it is necessary to add the corresponding reference in VBA to recognize the commands for the interface. The image on the left shows an example of RFEM 5.
The first part of the article series about the COM interface described opening and creating a model in RFEM. The second part explains creating and modifying elements on an example of a member. The elements described in Part 1 will not be explained again here.
Part 2.1 of the article series about the COM interface described creating and modifying elements on an example of a member. In the third part, these core elements are used again to create nodal supports, loads, load combinations, and result combinations. Thus, the model created in the second part will be extended. Therefore, the elements explained in Part 1 and Part 2.1 are not described again.
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.
With RFEM 5.06 and RSTAB 8.06, the examples and help files for programming the COM interface are not only available on the Internet, they are also included in the installation. To find them, look for the "SDK" folder in the project directory (usually C:\Users\Public\Documents\Dlubal).
Part 2.2 of the article series about the COM interface describes creating and modifying nodal supports, loads, load cases, load combinations, and result combinations on an example of a member. The fourth part explains creating individual tools.
In the construction process, it is often necessary to fabricate the concrete elements in sections. A classic example of this production in sections is the use of prefabricated downstand beams, in which the slab is completed in the onsite concrete construction. By creating a new concrete area, interfaces may arise between the already hardened concrete and the fresh concrete. The transfer of the longitudinal shear forces arising between the partial cross-sections must be considered in the design.
BIM is often used when it comes to data management in civil engineering. The individual disciplines of architecture, structural design, construction, and structural monitoring are coming closer together. Building Information Modeling makes this possible.. Dlubal Software provides a wide range of formats for data exchange. The following article explains the details of the interface with Autodesk Revit and, in particular, the export settings.
Sections 4.1 and 4.2 of this article series describe the optimization of a frame using the RF‑/STEEL EC3 add-on module. The fifth section explains how to link the module and get the relevant members. The elements already explained in the previous sections will not be described again.
Part 4.1 of this article series describes the connection of the RF‑/STEEL EC3 add‑on module; the members and load combinations to be designed were already defined. This section will focus on the optimization of cross‑sections in the module and the transfer to RFEM. The elements already explained in the previous parts are not described again.
Printout reports created in RFEM and RSTAB can be transferred to VCmaster using a direct interface and further processed there. VCmaster (formerly BauText) is a word processing program for engineers. Calculations, drawings, photos, and documents from various sources can be easily compiled, managed and used again with VCmaster.
This article discusses the most common BIM interfaces. Adjustments are often necessary during the transition to the structural branch-specific model. The tasks that arise and the tools to address them successfully and quickly are presented.
RF-COM/RS-COM is a programmable interface that allows the user to expand the main programs RFEM and RSTAB with customized input macros or post‑processing programs. A tool to copy and move selected guidelines in RFEM will be developed in this article. It is also possible to copy or move the guidelines to another work plane. VBA in Excel will be used as the programming environment.
An interface can be used to export the RFEM/RSTAB printout report to VCmaster and continue editing there. VCmaster is a word processing program for engineers.
The parts lists give information about which and how many parts are necessary for creating a building. They form the basis for identifying the needs and purchasing the components. Parts lists can be created in design modules, such as RF‑/STEEL EC3, RF‑/TIMBER Pro, and so on. Furthermore, a customized parts list can be created with the RF-COM/RS-COM interface.
When editing elements via the COM interface, selecting elements is often a problem because it cannot be carried out visually via the work window. The selection can be particularly difficult for models that have been created via the program interface and are then to be modified using a separate program. Apart from the exception, when the selection was made previously via RFEM, there are several alternatives for programming.
The calculation of structures based on digital twins is becoming an everyday task in the engineering office. If a digital building model already exists, you want to continue to use the information contained in it as seamlessly as possible. This states extensive requirements with regard to modeling and interfaces for BIM-compatible structural analysis software.
If you read out the results of a surface by means of the COM interface, you get a one-dimensional field with all results at the FE nodes or grid points. To get the results on the edge of a surface or along a line within the surfaces, you have to filter out the results in the area of the line. The following article describes a function for this step.
In RFEM and RSTAB, you can use many interfaces to simplify the modeling of your structure. From background layers, to the import of IFC objects that can be converted into members or surfaces, to the import of the entire structural system from Revit or Tekla. Regardless of the performance of the selected interface, further utilization also depends on the accuracy of the imported data.
It is necessary to design some structures in different configurations. It may be that an aerial work platform must be analyzed in its position on the ground as well as in the middle and in the extended position. Since such tasks require the creation of several models, which are almost identical, updating all the models with just one mouse click is a considerable relief.