Design procedure for double angles (Angles and tees: AISC 360)
The nominal flexural strength Mn is the lowest value obtained according to the limit states of yielding (plastic moment), lateral-torsional buckling and leg local buckling.
Mnx = Min {Mnx,Yield, Mnx,LTB, Mnx,LLB}
Note: For the local buckling check of
double angles under 360-05, the provisions of the 2010 code are used. In the 05
code, section F9.3 states “Flange local Buckling of Tees” and does not refer to
double angles.
In the case of biaxial bending, or bending and axial force the combined stress ratio must be checked using the provisions of AISC, section H2. The applied loads are
- Pr Axial
- Mrx Bending in x axis
- Mry Bending in y axis
Double Angles - Critical Points A, B & C