1. What is the Simple Wood Beam Equation?

The Simple Wood Beam equation calculates the maximum deflection (δ) of a simply supported beam under a uniform load. It's fundamental in structural engineering for assessing beam performance.

2. How Does the Calculator Work?

The calculator uses the Simple Wood Beam equation:

Where:

• \( \delta \) — Deflection (in)
• \( w \) — Uniform load (pounds per linear foot)
• \( L \) — Length of beam (feet)
• \( E \) — Modulus of elasticity (psi)
• \( I \) — Moment of inertia (in⁴)

Explanation: The equation shows deflection is proportional to the load and the fourth power of length, and inversely proportional to stiffness (EI).

3. Importance of Deflection Calculation

Details: Calculating deflection is crucial for ensuring structural integrity and serviceability. Excessive deflection can cause cracking, poor drainage, or discomfort.

4. Using the Calculator

Tips: Enter all values in the specified units. For wood beams, typical E values range from 1,000,000 to 1,800,000 psi depending on species and grade.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical acceptable deflection limit?
A: For wood floors, L/360 is common (e.g., 0.4" for 12' span). Roofs might allow L/240.

Q2: Does this account for shear deflection?
A: No, this is bending deflection only. For deep beams (depth/span > 1/5), shear deflection may need separate calculation.

Q3: How does moisture affect the calculation?
A: Wet wood has lower E values. Use appropriate adjusted values for wet service conditions.

Q4: What about concentrated loads?
A: This equation is for uniform loads only. Different equations apply for concentrated loads.

Q5: How to find moment of inertia (I) for common sizes?
A: For rectangular sections: I = (width × depth³)/12. Standard lumber I values are published in engineering references.