In the Surfaces tab of the 'Ultimate Configuration' or 'Strength Configuration' dialog, you can define basic settings for the design of surfaces.
The 'Design parameters' are grouped into categories that vary depending on the design standard.
Limit Values for Ignoring Internal Forces and Stresses
This category manages one or more limit values related to very small stresses. If the stress is below the defined ratio η, it is not considered in the design. The background to this option is described in more detail in the chapter Members | Basis.
Design Coefficients (for AISC)
If necessary, you can adjust the resistance factor Φ (for LRFD) and the safety factor Ω (for ASD) to be used for the design of surfaces.
Importance Factor of Structure (for GB)
In this section, you can, if necessary, adjust the factor γ0 by which the design values of the internal forces are multiplied. This factor is regulated in GB 50017, 3.1.9, GB 50018, 4.1.3, and GB 51022, 3.1.3. For more information, see the standards GB 50068 and GB 50009.
Partial Safety Factor of Materials from Another Standard (for GB)
If required, you can adjust the partial safety factor for the material strength (see image Steel design according to GB 50017): Select the 'User-defined' check box and specify the factor γR.
Options
Optionally, the plastic strain design can be performed for surfaces. This option is available for all design standards. For EN 1993, the design is performed according to the maximum allowable plastic strain, as defined for areas under tensile stresses according to EN 1993-1-5 [1] C.8(1). The recommended limit strain εpl,lim is 50 ‰.
