Steel Columns subject to axial force and flexure about both axes design are explained in detail under this title.
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Symbols
Pr = required axial strength determined using LRFD or ASD load combinations, kips (N)
Pc = available axial strength, kips (N)
Mr = required flexural strength, determined using LRFD or ASD load combinations, kip-in. (N-mm)
Mc = available flexural strength, kip- in. (N-mm)
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Design for Axial Force and Flexural Moment
The strength calculation considers the combined stresses created in the elements under flexural and axial force.
The superposition of the stresses only applies to similar stresses.
The superposition rule does not apply to stability losses.
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Design with AISC 360-16
Equation H1.1 is used for biaxial and single symmetry axis members under the influence of axial compression and flexural moment.
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Design axial strength,
(LRFD)Mathinline body $$ \normalsize P_c =\phi_c P_n $$ Allowable axial strength
(ASD)Mathinline body $$ \normalsize P_c =P_n/ \Omega_c $$ Design flexural strength,
(LRFD)Mathinline body $$ \normalsize M_c =\phi_b M_n $$ Allowable flexural strength
(ASD)Mathinline body $$ \normalsize M_c =M_n/ \Omega_b $$
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