1331x
000582
2023-12-04

Member Transverse Stiffeners

Member transverse stiffeners can be taken into account in the shear resistance design of web plates in order to limit the buckling panels. Further design checks, for example, for concentrated load introduction, are not performed.

Assignment to Member or Member Set

Member transverse stiffeners are organized in RFEM and RSTAB as a "Type for Members". Thus, you can assign the member transverse stiffeners to one or more members by using the Edit Member dialog box, by selecting them in the Member Transverse Stiffener dialog box, or via the input table. The assignment is done similarly to the procedure described in Chapter Types for Aluminum Design.

Furthermore, it is possible to assign the member transverse stiffeners to a member set. The relative position of the stiffener types refers then to the length of the entire member set. Note that a member transverse stiffeners can be assigned either to a member or to a superordinate member set.

Stiffener Type and Location

In the Stiffener Type and Position section, specify all stiffener types and their locations. Click the Relative/Absolute Input button to switch between the absolute and relative input of the position. Click the Sort button to sort the list according to the positions.

Info

The entered positions apply to all members with the member transverse stiffeners assigned. If the members have different lengths, the absolute and relative position entries differ. An automatic conversion is not possible in that case.

The following types are currently available:

  • Flat stiffeners
  • End plates at the member start and end
  • Channel sections
  • Angle sections (connection of both legs to the stiffened web)
  • Connecting columns at the member start and end
  • Warping restraints

Some stiffener types (such as flat stiffeners) require entering the stiffener position (left, right, or double-sided). In this case, the left side means the side lying in the negative y-direction.

Select the "Multiple" check box to add more stiffeners of the same type to a beam. In the parameters, you can now specify the number of stiffeners and the offset recurrence.

Parameters

In this section of the dialog box, you define the main properties of each stiffener type. In most cases, this requires the information about the material and dimensions of the stiffener.

To include a stiffener in the design in the add-on, select the "Consider Stiffener in Design Add-ons" check box. Depending on the selected design standard, this option is not available for all stiffener types. It may be necessary to classify the stiffener with regard to its plasticity.

Important

Only the stiffeners with the activated option to "Consider Stiffener in Design Add-ons" are considered in the design.

Warping Restraint

If the Torsional Warping (7 DOF) add-on has been activated, the member transverse stiffeners are used to define warping restraints when calculating members with 7 degrees of freedom. More information can be found in Chapter Member Transverse Stiffeners of the manual for this add-on.

Info

When calculating members with 6 degrees of freedom, member transverse stiffeners have no impact on the system stiffness.

If you want to use the member transverse stiffeners for the design in Aluminum Design, the resulting warping restraints spring stiffness is only displayed as information. There is no automatic transfer to the input windows of nodal supports in the Effective Lengths dialog box.