Steel design

Expanded regulatory framework for verification and design of variable cross-section bars.

In the design mode of LIRA-FEM, analysis of variable cross-sections has been added: as beams, columns, truss elements, or universal bars — according to DBN V.2.6-198:2014 and EN 1993-1-1:2005/AC:2009.

The section itself can be symmetric or asymmetric by varying flange or web geometric characteristics according to a linear law.

Implemented calculation of angles along axes parallel to flanges or relative to principal axes, including calculation of cruciform sections composed of symmetric or asymmetric angles along principal axes or axes parallel to flanges, as beams, columns, or universal bars.

Verification and design of angle sections are performed considering their specific behavior under different force characteristics according to DBN V.2.6-198:2014 and “Design Manual for Steel Structures (to SNiP II-23-81*)”.

For bar finite elements with cross-sections of single angle L and cruciform angles ⌐└, whose flanges are arranged parallel to global axes in the design model, calculation in principal axes has been added.

This option is implemented as an additional check box when selecting the section type Angle parallel to flanges.

Added new steel tables:

• Ukraine: angles (DSTU EN 10056-1:2006), hollow and circular tubes (DSTU EN 10219-2:2009), expanded steel tables for channels and I-beams (EN 10365:2022);
• India: hollow tubes (IS 4923-1997), circular tubes (IS 3601-2006), I-beams (IS 808:1989, IS 12778:2004), channels, tees, and angles (IS 808:1989);
• China: I-beams (GB/T 11263-2017), channels (GB/T 706-2016), C-sections (JG/T 380-2012), angles (GB/T 706-2016, JG/T 380-2012), circular tubes, tees (GB/T 11263-2010), hollow tubes (GB/T 6728-2017), Z-sections (GB 50018-2002).

In local STC mode, the ability to sort by columns in the Design forces and Element deflections tables has been added.