The standards specify the relevant size and distributions that lead to efficient and reliable design checks. RF‑/FE‑LTB provides various settings for the standardization of a mode shape. We recommend graphically checking the imperfections applied in the calculation. You can display them in the Results Navigator.
Imperfections
Stability design according to the second-order analysis requires imperfections to be applied.
Links
Do you have any questions?
![System and Loading](/en/webimage/008936/577926/01-en.png?mw=512&hash=65e98cfe859ce35a3e3e9da47a0ef9335401520e)
The critical factor for lateral-torsional buckling or the critical buckling moment of a single-span beam will be compared according to different stability analysis methods.
![Eccentric Nodal Loads in RF-/FE-LTB](/en/webimage/009883/2420951/01-en-png-png.png?mw=512&hash=6ca63b32e8ca5da057de21c4f204d41103e6fe20)
There are two ways to specify eccentric nodal loads in RF-/FE-LTB. First, the nodal load has to be applied in the right direction. Then, you can assign either the resulting torsional moment or the eccentricity.
![Imperfections](/en/webimage/009948/2421508/01-en-png-png.png?mw=512&hash=6ca63b32e8ca5da057de21c4f204d41103e6fe20)
Stability design according to the second-order analysis requires imperfections to be applied.
![Critical Load Factor of Tapered Steel Frame 2: Calculation in RF-/FE-LTB](/en/webimage/010007/2422008/01-en-png-9-png.png?mw=512&hash=5737f44b31a0883cd584e5e0da784bf91a036347)
The stability analysis of the steel frame described in my previous post can also be performed in RF‑/FE‑LTB according to the Equivalent Imperfection Method. This post describes how to calculate or determine the critical load factor.
![Add-on "Steel Joints for RFEM 6" | Component Library](/en/webimage/043097/3898884/steel_joints_components.png?mw=512&hash=e4f835906155863fc7019d5043b22e553dc766f9)
- Numerous component types, such as base and end plates, web angles, fin plates, gusset plates, stiffeners, tapers, or ribs for easy input of typical connection situations
- Universally applicable basic components (such as plates, welds, bolts, auxiliary planes) for modeling complex connection situations
- Graphical display of the connection geometry with dynamic updating during the input
- Wide range of cross-section shapes: I-sections, U-sections, angles, T-sections, hollow sections, built-up cross-sections and thin-walled sections
- Library in the Dlubal Center with a large number of program-side template connections, including user-defined templates
- Automatic adaptation of the connection geometry based on the relative arrangement of the components to each other – even in case of subsequent editing of the structural components
![Feature 002820 | Limit Plastic Strain for Welds](/en/webimage/050344/3881226/1.png?mw=512&hash=9d7f6c198b6d4ae6ee8f2fa8bca75f85579e14c9)
In the ultimate configuration of the steel joint design, you have the option to modify the limit plastic strain for welds.
![Component "Base Plate"](/en/webimage/050345/3936120/50345.png?mw=512&hash=3bd641cb1a2445804b338855e4debfc40c6563e9)
The "Base Plate" component allows you to design base plate connections with cast-in anchors. In this case, plates, welds, anchorages, and steel-concrete interaction are analyzed.
![Feature 002807 | 3D Display of FSM Results](/en/webimage/049281/3861162/2024-05-01_10-32-55.png?mw=512&hash=2377d291bc20ac3d78d617b50c131614e99ac6f7)
In the "Edit Section" dialog box, you can display the buckling shapes of the Finite Strip Method (FSM) as a 3D graphic.
Recommended Products for You