You can access the Global Settings of the Steel Design via the shortcut menu in the navigator entry or by clicking the button above the Steel Design input tables. This chapter describes the settings available in this dialog box. They are independent of the design standard, but the standard values can differ. By clicking the button, the standard setting of the dialog box is restored according to the selected design standard.
Configurations to Calculate
The design is preset in all available configurations. However, if you do not want to perform serviceability limit state design, for example, you can deactivate the serviceability configuration here. Thus, no serviceability limit state design checks are carried out and the input data for the steel design is reduced accordingly. Design situations that are assigned to a deactivated configuration are no longer taken into account in the design. A design situation can be assigned in the Design Situations table.
Analysis Method
This section controls how the design internal forces of the load and result combinations are transferred to the design. The following analysis methods are available:
- Enumeration Method
- Envelope Method
- Mixed Method
Enumeration Method
The "Enumeration Method" allows for the individual calculation of all load and result combinations included in a design situation. This usually leads to the most accurate results, but may also lead to increased calculation time.
Envelope Method
In the case of the "Envelope Method", the enveloping internal forces of all load and result combinations included in a design situation are calculated and then used for the design checks. Compared to the "Enumeration Method", this usually results in a shorter calculation time.
Mixed Method
For the "Mixed Method", you can define an upper limit for the number of load and result combinations of a design situation, for which you want to design according to the "Enumeration Method". If the number of load and result combinations exceeds this upper limit, the design is carried out according to the "Envelope Method".
Check of Member / Member Set Slendernesses
As part of the steel design, you can also check the slenderness of members and member sets subjected to tension, compression, or bending. The limit values to be checked are specified here. If there are effective lengths defined for the members or member sets to be designed, they are taken into account when calculating the slenderness. The evaluation is carried out in the Slenderness result tables.
Optimization - Maximum Allowable Design Ratio
Within the add-on, it is possible to carry out an optimization of standardized cross-sections (see Chapter Cross-Sections). When checking the possible variants, the utilization of the variant is compared with the maximum value defined here.
Storing Results
For complex structures with several thousand members, the result files can become very large if all results are saved in them. Depending on the selected setting, a result is saved for each location, for each stress point, or for each object, and the file size can be reduced accordingly. Notwithstanding the above, you can display all results in the program, since the missing results are recalculated automatically.
Settings for Sections
Some design standards indicate sections that can only be used for closed or open cross-sections. The distinction between the open and closed cross-sections with a general cross-section shape is made by considering the Bredt component of the total torsional moment of inertia. In the case of closed cross-sections, the total torsional moment of inertia results almost entirely from the Bredt component.