Page 315 - Advanced Design Examples of Seismic Retrofit of Structures

304 Advanced Design Examples of Seismic Retrofit of Structures

FIG. 5.9 A view of the models. (A) Main building. (B) Sports building.

where:
L b ¼distance between points braced against lateral displacement of the
compression flange, or between points braced to prevent twist of the cross sec-
tion, per AISC 360 [8];
L p ¼limiting lateral unbraced length for full plastic bending capacity for
uniform bending from AISC 360;
M pCE ¼expected plastic moment capacity; and
F ye ¼expected yield strength of the material.
Based on the Iranian National Building Code; Part 10: Steel Building [6], the
flexural members are considered braced if the free distance of the compression
flange is smaller than the minimum of the results of Eqs. (5.21) and (5.22).