Beam deformation

Euler-Bernoulli Beam Deflection

This interactive visualization demonstrates the deflection \(w(x)\) of beams under concentrated loads, computed using Euler-Bernoulli beam theory.

How to use

  1. Select a support configuration from the dropdown menu
  2. Enter a position along the beam (0 to 10)
  3. Enter the force magnitude (positive = downward)
  4. Click “Add force” to apply the load
  5. Observe how the deflection curve changes

Available support configurations

Configuration Left End Right End Description
Cantilever Clamped Free Fixed at one end, free at the other
Simply supported Hinged Hinged Supported at both ends, free to rotate
Fixed-fixed Clamped Clamped Both ends fully restrained
Propped cantilever Clamped Hinged Fixed at one end, simply supported at the other

Theory

The Euler-Bernoulli beam equation relates the deflection \(w(x)\) to the bending moment \(M(x)\):

\[ EI \frac{\mathrm{d}^2 w}{\mathrm{d} x^2} = -M(x) \]

where:

  • \(E\) is Young’s modulus
  • \(I\) is the second moment of area
  • \(EI\) is the bending stiffness

Boundary conditions

The different support types impose the following boundary conditions:

Clamped end: \[ w = 0 \quad \text{and} \quad \frac{\mathrm{d}w}{\mathrm{d}x} = 0 \]

Hinged end: \[ w = 0 \quad \text{and} \quad M = EI\frac{\mathrm{d}^2 w}{\mathrm{d}x^2} = 0 \]

Free end: \[ M = 0 \quad \text{and} \quad V = -EI\frac{\mathrm{d}^3 w}{\mathrm{d}x^3} = 0 \]

Example: Cantilever with end load

For a cantilever beam of length \(L\) with a concentrated force \(F\) at the free end:

\[ w(x) = \frac{F x^2}{6EI}(3L - x) \]

The maximum deflection occurs at the free end:

\[ w_{\max} = \frac{F L^3}{3EI} \]