Question:

How SACS calculates torsion stress on I-beam members (flange warping bending)?

Answer:

Torsional Constant (J) of Wide Flange Sections:

Knowing b = 100 mm, tf = 10 mm, tw = 6 mm, d = 100 mm, and R = 6 mm:

=0.1143,1=13.68182 ,=76237.16 2 → The calculated J value is listed as 7.6 (cm4) in PostVue database and 7.624 (cm4) in listing file database.


Bending of the flange about z axis due to z axis due to torsion:

Knowing Mx = -1 KN.m, h = b – tf = 90 mm, L = 1 m, and Iz = 166.8 cm4:

#Please check out section 3.2.1.2 Wide Flange Sections under Post manual document