With Dlubal Software, you always have an overview, regardless of whether your projects are from the reinforced concrete, steel, timber, aluminum, or other industry. The program clearly displays the design check formulas used in your design (including a reference to the used equation from the standard). These design check formulas can also be included in the printout report.
When performing a design according to EN 1993‑1‑3, it is possible to graphically display a mode shape for the distortional buckling of a cross-section, and for the RSECTION cross-sections.
The mode shape can also be output in RSECTION 1 for library cross-sections.
The design of cold-formed steel members according to the AISI S100-16 / CSA S136-16 is available in RFEM 6. Design can be accessed by selecting “AISC 360” or “CSA S16” as the standard in the Steel Design Add-on. “AISI S100” or “CSA S136” is then automatically selected for the cold-formed design.
RFEM applies the Direct Strength Method (DSM) to calculate the elastic buckling load of the member. The Direct Strength Method offers two types of solutions, numerical (Finite Strip Method) and analytical (Specification). The FSM signature curve and buckling shapes can be viewed under Sections.
The new steel sections according to the latest CISC Handbook (12th edition) are available in RFEM 6. The sections are listed in the Standardized library. In the filter, select “Canada” for the region and “CISC 12” for the standard. Alternatively, the section name can be directly entered in the search box located at the bottom of the dialog box.
The governing component temperature at the time of analysis can be determined for the fire resistance design automatically using the input. In this case, you can follow the temperature curve in detail as a function of timeby displaying the temperature-time diagram.
Compared to the RF‑/STEEL EC3 add-on module (RFEM 5 / RSTAB 8), the following new features have been added to the Steel Design add-on for RFEM 6 / RSTAB 9:
In addition to Eurocode 3, other international standards are integrated (such as AISC 360, CSA S16, GB 50017, SP 16.13330)
Consideration of hot-dip galvanizing (DASt guideline 027) in the fire protection design according to EN 1993‑1‑2
Input option for transverse stiffeners that can be taken into account in the shear buckling analysis
Lateral-torsional buckling can also be checked for hollow sections (for example, relevant for slender, high rectangular hollow sections)
Automatic detection of members or member sets valid for the design (for example, automatic deactivation of members with invalid material or members already contained in a member set)
Design settings can be adjusted individually for each member
Graphical display of the results in the gross section or the effective section
Output of the used design check formulas (including a reference to the used equation from the standard)
The Torsional Warping (7 DOF) add-on provides you with numerous new possibilities. For example, you can perform the calculation of member structures in RFEM and RSTAB, taking into account the cross-section warping. You can consider the resulting internal forces (N, Vu, Vv, Mt,pri, Mt,sec, Mu, Mv, Mω) in the equivalent stress analysis of the steel design. Please note: This feature is currently not available for the design standards AISC 360‑16 and GB 50017.
You can select several methods that are available for the eigenvalue analysis:
Direct Methods
The direct methods (Lanczos [RFEM], roots of characteristic polynomial [RFEM], subspace iteration method [RFEM/RSTAB], and shifted inverse iteration [RSTAB]) are suitable for small to medium-sized models. You should only use these fast solver methods if your computer has a larger amount of memory (RAM).
In contrast, this method only requires a small amount of memory. Eigenvalues are determined one after the other. It can be used to calculate large structural systems with few eigenvalues.
Use the Structure Stability add-on to perform a nonlinear stability analysis using the incremental method. This analysis delivers close-to-reality results also for nonlinear structures. The critical load factor is determined by gradually increasing the loads of the underlying load case until the instability is reached. The load increment takes into account nonlinearities such as failing members, supports and foundations, and material nonlinearities. After increasing the load, you can optionally perform a linear stability analysis on the last stable state in order to determine the stability mode.
Did you use the eigenvalue solver of the add-on to determine the critical load factor for the stability analysis? Verz well, you can then display the governing mode shape of the object to be designed as a result. The eigenvalue solver is available for the lateral-torsional buckling analysis, depending on the design standard used. You can also use the internal eigenvalue solver for the general method according to EN 1993‑1‑1, 6.3.4.
Do you want to perform a stability analysis in the Steel Design add-on? Then it is absolutely necessary to define the effective lengths. To do this, define the nodal supports and effective length factors in the input dialog box. For easy documentation and a comprehensible check of the entries, you can also graphically display the nodal supports and the resulting segments with the corresponding effective length factor in the work window of RFEM/RSTAB.