By assigning a serviceability configuration to an object, you can define the limit values to be checked for the design. The basic structure of the design configuration dialog box and the option of assigning it to the individual objects are described in the superordinate chapter Steel Design .
Serviceability Limits
Deflection limits are defined as a small part of the reference length. In this case, a distinction is made between a beam supported on both sides and a cantilever beam. For a certain segment, the type is automatically determined based on the assigned design supports. A segment with design supports on both sides or without design supports is regarded as a beam; a segment with a design support on one side as a cantilever. The reference lengths and design supports of the objects can be defined in the Design Supports & Deflection tab.
Depending on the selected design standard, various design situation types are available for the serviceability limit state design checks. A separate limit value can be defined for each combination type. In the case of the design according to EN 1999‑1‑1, a distinction is made between the characteristic, the frequent, and the quasi-permanent combinations, for example. The limit values entered in the standard values for EN 1993‑1‑1 are only suggestions at first, as there are no fixed limit values specified in the standard itself.
Vibration Design (for EN 1993-1-1 only)
By entering the limits for vibration design, you can easily check the vibration amplitude. All design situations of the "Vibration" category are checked within the design (the selection is made in the table of Design Situations). It is assumed that these are appropriate load combinations or result combinations that contain the maximum values of the vibration amplitudes in the form of deflections. They are compared to the entered limit value.
Limitation of Web Breathing (for EN 1993-1-1 only)
You can check the web slenderness according to EN‑1993‑2, Section 7.4, by activating the frequent SLS combinations. Depending on the option selected, a limit value for railroad bridges or road bridges is used for the design. If you have assigned member transverse stiffeners to the object to be designed and activated this for the design add-on, the distances between the transverse stiffeners are used for the web breathing design. The reference length Lz from the Design Supports & Deflection tab is used as the reference length in the design.