§13.2 Bracing Members

The unbraced length of a brace is considered to be the length between the nodes at the brace ends.

To perform the lateral force distribution checks on SCBFs, the engineer is required to assign the same frame number to all the braces in the same line of bracing. Also, the Use Frame Nos. to Designate a Frame Line option must be selected in the Seismic Code Dialog obtained by selecting the Criteria-Codes command.

§13.2d Width-Thickness Ratios

Per Supplement No. 2 the b/t ratios of stiffened and unstiffened elements are checked against the compactness requirements in LRFD specification Table B5.1. Also, b/t of angles are not allowed to exceed 52/√fy, I-Shaped members and channels will be checked with λp in Table I-9-1.