Back to Calculators

Beam Deflection Simulator

Interactive beam bending visualization for simply supported and cantilever beams

About this Simulator

This interactive simulator visualizes beam bending behavior in real-time. Watch how beams deflect under load with accurate deflection curves, reaction forces, and bending moments displayed. The deflection is magnified for visibility while showing actual calculated values.

Physics & Formulas

Simply Supported (Center Load):

$$\delta_{max} = \frac{P L^3}{48 E I}$$

Cantilever (End Load):

$$\delta_{max} = \frac{P L^3}{3 E I}$$

Bending Moment:

$$M_{simply} = \frac{PL}{4}, \quad M_{cantilever} = PL$$

How to Use

  1. Adjust the Applied Load slider to see how deflection changes with force
  2. Change Beam Length to visualize different span scenarios
  3. Modify Elastic Modulus for different materials (Steel ~200 GPa, Aluminum ~70 GPa)
  4. Adjust Moment of Inertia to simulate different cross-sections
  5. Switch between Simply Supported and Cantilever beam types
  6. Toggle Show Deflection Curve to highlight the neutral axis
  7. Toggle Show Forces to see reaction forces and moments
  8. Click Animate to see dynamic loading behavior

Frequently Asked Questions

What is an acceptable deflection?

Typical limits: L/360 for floor beams, L/240 for roof beams, L/180 for cantilevers. More stringent limits (L/500) may apply for precision equipment or sensitive finishes.

How do I find moment of inertia?

Use steel section tables (AISC, Eurocode). For rectangular sections: I = bh³/12. For circular sections: I = πd⁴/64. I-beams have much higher I values for the same weight.

Why is deflection important?

Excessive deflection causes serviceability issues: cracked finishes, sagging appearance, door/window binding, and equipment malfunction. Deflection limits ensure structural adequacy.

Inputs

10
3
200
5000