In the Lateral buckling parameters field of the Member Definition - Parameters (SANS 10162-1:2011) dialog you can specify om2. This coefficient is used to account for increased moment resistance of a laterally unsupported doubly symmetric beam segment when subject to a moment gradient (as specified in Section 13.6 of the code). It can be defined manually, by typing a value from the range (1.0, 2.5) in the om2= field, or by selecting one of the icons from the Coefficient om2 dialog. To open this dialog, click the icon next to the om2= field.
You can select one from 3 icons:
- If this icon is selected, during the member verification
Robot calculates the ω2 coefficient based on the bending moments at characteristic points of the member (general method 13.6 (a).(ii)).
- If this icon is selected,
Robot calculates the ω2 coefficient based on the value of bending moments at the member ends (used for linear distribution of bending moments).
- If this icon is selected,
Robot uses ω2= 1.0 for calculations.