Inputs
Assumes simply supported beam, small-deflection linear theory. For critical applications or complicated load paths/supports, consult a structural engineer.
Results
Material: Steel A36
E: 29.0 Mpsi
Allowable σ (after SF): 14.4 ksi
Span L: 48 in
Load: 500 lb
Limit: L/360 (δ≤0.133″)
Required section properties
Mmax: 6,000 lb·in
Sreq: 0.417 in³
Ireq: 0.298 in⁴
Flat (rectangular) recommendation
Width b: 2.000 in
t (from strength): 1.118 in
t (from deflection): 1.214 in
Recommended thickness:
1.250″ (rounded to the nearest 1/16″).
For flat bars, formulas use strong-axis bending: S = b·t²/6 and I = b·t³/12. Increase width or thickness as needed; verify support and load details.