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Beam deflection calculates downward displacement under loading. Engineers use this to ensure beams don't sag excessively and meet serviceability requirements.

Formel

The calculator applies beam deflection formulas: δ = PL³/(3EI) for cantilever

Trin-for-trin guide

  1. 1Input beam type (cantilever, simply supported, etc.), load type, material properties, and geometry
  2. 2The calculator applies beam deflection formulas: δ = PL³/(3EI) for cantilever
  3. 3Results show maximum deflection and compliance with limits

Løste eksempler

Input
Cantilever, P=10 kN, L=3 m, EI=200 kN·m²
Resultat
δ ≈ 45 mm
At L/4 deflection check

Almindelige fejl at undgå

  • Using beam formula for wrong support conditions
  • Neglecting distributed loads when present

Ofte stillede spørgsmål

Why limit beam deflection?

Excessive deflection causes floor sag, cracks, misalignment. Building codes limit deflection to L/240-L/360.

How does moment of inertia affect deflection?

Doubling I reduces deflection by half; this is why tall I-beams resist deflection better than wide ones.

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