When calculating the allowable stress (ASD 9th) or moment capacity (AISC 360 ASD and LRFD, LRFD 3^rd) of an unbraced segment, the program calculates Cb based on the end moments of the segment. Although not required by Code, you may conservatively specify that Cb be set equal to 1.0 for all simple span noncomposite beams. You may also specify that Cb be set equal to 1.0 for all cantilevers, as recommended by the Codes and other sources. Otherwise, the program will calculate and use the values of Cb as allowed by the appropriate Code.

The output shows the values of stress/capacity, unbraced length, and Cb at the points of maximum and minimum moments as well as the controlling condition. Note that the controlling condition may not correspond to any of the maximum or minimum moment conditions; this indicates that the controlling condition occurs in a segment with a lesser moment but greater unbraced length.