Steel Beam Design Example with LTB Check
Steel beam flexural design example per AISC 360-22 Chapter F. Determines Lp and Lr, classifies the unbraced length into the inelastic LTB zone, and computes nominal moment Mn using the linear interpolation equation.
Given Parameters
Fy = 50 ksi
plastic section modulus
elastic section modulus
effective LTB radius
torsion constants
unbraced length; moment gradient
factored moment demand
Calculation Steps
1. Plastic Moment and Lp
2. Elastic LTB Limit Lr
3. Classify and Compute Mn
4. Design Strength
Demand / Capacity Ratio
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