If axial compression exists, the member is assessed for Flexural Buckling and for Torsional and Flexural Torsional buckling.

The compressive strength is determined in accordance with Equations E3.1 and E4.1. For double angles these equations are subject to the modifications of Section E6.

The member length or member sub lengths between braces are checked for:

• Flexural buckling about major axis - for each unbraced length between adjacent points of major axis lateral brace and or torsional brace.

• Flexural buckling about minor axis - for each unbraced length between adjacent points of minor axis lateral brace and or torsional brace.

• Torsional and flexural torsional buckling - for each unbraced length between adjacent points of torsional brace (this check is not applied to hollow sections.)

For any unbraced length, the required compressive force P_r is taken as the maximum compressive force in the relevant length.

A warning is issued if the slenderness ratio KL/r exceeds 200.