Beam Deflection Calculator

Calculate Beam Deflection

About Beam Deflection

Beam deflection calculations are essential for structural engineering to ensure beams can safely support loads without excessive bending.

Deflection Formula:

δ = (Load × Length³) / (K × E × I)

Where:

  • δ = Deflection
  • E = Modulus of Elasticity
  • I = Moment of Inertia
  • K = Support condition factor

Support Conditions:

  • Simply Supported: K = 48
  • Cantilever: K = 3
  • Fixed-Fixed: K = 192
  • Fixed-Pinned: K = 48

Common Materials:

• Steel: E = 29,000,000 psi
• Concrete: E = 3,000,000 psi
• Wood: E = 1,800,000 psi
• Aluminum: E = 10,000,000 psi

Allowable Deflections:

• L/240 for live loads
• L/180 for total loads
• L/300 for brittle finishes
• L/360 for plaster ceilings

Proper deflection calculations ensure structural safety and serviceability requirements are met in building design.