Contact Solids: "Side surfaces do not have four boundary curves"
In RFEM, you can display the contact properties between two surfaces by means of contact solids.
When modeling contact solids, you should keep in mind that each connecting side surface between the contact surfaces is to be modeled as a simple surface with four boundary lines.
The FE mesh cannot be generated if this modeling rule is not considered. In that case, the program displays the following error message: "Side surface [Surface No.] does not have four boundary curves".
The contact solid shown in Figure 1 has contact surfaces F5 and F6 and side surfaces F1 to F4. Side surfaces F1 to F3 each have four boundary lines. Side surface F4 has six boundary lines (Lines 1 through 6) and thus does not correspond to the modeling rule, so the error message is displayed.
Lines 2 and 3, as well as 5 and 6, can now each be merged into one line, so that side surface F4 only consists of four boundary lines (Figure 2).
If it is impossible to merge the lines because, for example, other elements are connected, side surface F4 would have to be divided into several partial surfaces, each consisting of only four boundary lines. In Figure 3, side surface F4 has been divided into partial surfaces F4 and F7, making it possible to generate the FE mesh.
Sonja von Bloh, M.Sc.
Product Engineering & Customer Support
Ms. von Bloh provides technical support for our customer and is responsible for the development of the SHAPE‑THIN program.
Do you have questions or need advice?
Contact our free e-mail, chat, or forum support or find various suggested solutions and useful tips on our FAQ page.
This article compares it with the following article: Design of concrete columns subjected to centric compression with RF-CONCRETE Members . It is therefore a question of taking exactly the same theoretical application carried out on RF-CONCRETE Members and reproducing it on RF-CONCRETE Columns. Thus, the objective is to compare the different input parameters and the results obtained for the two additional modules for the design of column -type concrete members.
Depending on stiffness, mass, and damping, structures react differently to wind action.
- Could you please explain where do I increase the calculated forces in the work window? They are so small that I cannot recognize them.
- In RF‑/DYNAM Pro, the Rayleigh damping is available. How do I determine and use these factors?
- What do I have to consider when installing and starting the programs by Dlubal Software?
- There are two solving methods for a linear time history analysis available in the RF‑/DYNAM Pro add-on module. What is the difference between them?
- How can I apply a load on a partial area of a rotationally symmetric structural component only?
- I design a cross-section created in the SHAPE‑THIN program by using the design add-on module, but the program shows the error message "ER006 Invalid type of c/t-part for cross-section of type General." What can I do?
- After running the program as a full version and working with it for a certain period of time, an error message appears when saving the file, saying that the authorization failed. What is the reason and how can I save my file anyway?
- What method is applied in the RF‑/DYNAM Pro - Equivalent Loads add-on module?
- Which type of file is used for RFEM and RSTAB?
- I obtain different results when comparing the deformation analysis in the RF‑CONCRETE add-on modules and another calculation program. What could be the reason for this?
Structural engineering software for finite element analysis (FEA) of planar and spatial structural systems consisting of plates, walls, shells, members (beams), solids and contact elements