Design the column under the influence of axial force, the properties of which are given in the figure below, using the AISC 360-16.
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Solution:
Local Buckling
a) For flange:
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b) For web:
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Flexural Buckling
According to article 6.4.3(a) of the regulation, K= 1.0 is taken.
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LRFD:
Mathinline body $$ \normalsize P_d=
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\phi_c*P_n=0.90*5316.27=4784.64 kN$$ ASD:
Mathinline body $$ \normalsize P_d=P_n/Ω_c=5316.27/1.67=3183.4 kN$$
Required Compressive Force Strength
LRFD:
Mathinline body $$ \normalsize P_u=1.2P_G+1.6P_Q=1.2*750+1.6+2000=4100 kN$$ ASD:
Mathinline body $$ \normalsize P_a=P_G+P_Q=750+2000=2750 kN$$
PMM Ratio
LRFD:
Mathinline body $$ \normalsize P_u=P_d=4100/4784.64=0.86 $$ ASD:
Mathinline body $$ \normalsize P_a=P_d=2750/3183.4=0.86 $$
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