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153x
000889
2023-12-29

Limiting Unbraced Length

For the limit state of inelastic lateral-torsional buckling and doubly symmetric I-shaped members

Lr = 1.95 · rts · E0.7 Fy · J · CSxho + JcSxho2 + 6.76 0.7FyE2

E

Modulus of elasticity

Fy

Yield strength

J

Torsional constant 

Sx

Elastic section modulus taken about the x-axis 

ho

Distance between the flange centroids
;