Moment-curvature curves may be obtained for a given section and axial load through the following process:
- Create the section using the Section Designer.
- Select Display > Show Moment-Curvature Curve to display the moment-curvature curve for a default axial force of zero (Figure 1).
- Enter the desired axial force (P), then select Refresh to generate the curve for a specific axial load.
Figure 1 - Moment-curvature curve
Angle (Deg) specifies the orientation of the neutral axis, measured counterclockwise from the negative 3 axis, as shown in Figure 2. Moment-curvature formulation then determines the location of the neutral axis. Neutral-axis location is measured along an orthogonal projection from the neutral axis to the section centroid.
Figure 2 - Neutral-axis location