Knowledge Base

The modal relevance factor is a result of the linear stability analysis and qualitatively describes the degree of participation of individual members in a specific mode shape.

For the serviceability of a structure, the deformations must not exceed certain limit values. This article describes an example that shows how to analyze the deflection of members using Dlubal's design add-ons.

To be able to evaluate the influence of local stability phenomena of slender structural components, RFEM 6 and RSTAB 9 provide you with the option of performing a linear critical load analysis on the cross-section level. The following article explains the basics of the calculation and the result interpretation.

Custom sections are often required in cold-formed steel design. In RFEM 6, the custom section can be created using one of the “Thin-Walled” sections available in the library. For other sections that do not meet any of the 14 available cold-formed shapes, the sections can be created and imported from the standalone program, RSECTION. For general information on AISI steel design in RFEM 6, refer to the Knowledge Base article provided at the end of the page.

RFEM 6 offers the Aluminum Design add-on for the design of aluminum members. This article shows how class 4 sections are designed according to Eurocode 9 in the program.

The design of cold-formed steel members according to the AISI S100-16 is now available in RFEM 6. Design can be accessed by selecting “AISC 360” as the standard in the Steel Design add-on. “AISI S100” is then automatically selected for the cold-formed design (Image 01).

Member transverse stiffeners are available as an option when editing members in RFEM 6 and RSTAB 9. They can be taken into account when verifying the shear resistance of web plates in order to limit the buckling fields. In RFEM 6 and RSTAB 9, member transverse stiffeners are organized as “Type for Members” (Image 1).

An aluminum member section comprised of slender elements may experience local buckling failures of its flanges or web before the member can reach its full strength. In the Aluminum Design add-on, there are three options available for determining the nominal flexural strength, M_nlb for the limit state of local buckling when designing according to the 2020 Aluminum Design Manual [1].

RFEM 6 offers the Aluminum Design add-on to design aluminum members for the ultimate and serviceability limit states according to Eurocode 9. In addition to this, you can perform design according to ADM 2020 (US Standard).

Structures in RFEM 6 can be saved as blocks and reused in other RFEM files. The advantage of dynamic blocks with respect to non-dynamic blocks is that they allow interactive modifications of the structural parameters as a result of modified input variables. One example is the possibility to add structural elements by changing only the number of bays as an input variable. This article will demonstrate the aforementioned possibility for dynamic blocks that are created by scripting.