1. What is Bearing Stress?

Bearing stress (σ_b) is the compressive stress that develops at the interface between two contacting surfaces, such as between a bolt and a plate in a bolted joint. It represents the force per unit area acting perpendicular to the contact surface.

2. How Does the Calculator Work?

The calculator uses the bearing stress formula:

Where:

• \( \sigma_b \) — Bearing stress (Pa or psi)
• \( P \) — Applied load (N or lb)
• \( d \) — Bolt diameter (m or in)
• \( t \) — Plate thickness (m or in)

Explanation: The formula calculates the compressive stress by dividing the applied load by the projected contact area (diameter × thickness).

3. Importance of Bearing Stress Calculation

Details: Accurate bearing stress calculation is crucial for designing bolted connections, pinned joints, and other mechanical assemblies to prevent material failure, deformation, or excessive wear at contact surfaces.

4. Using the Calculator

Tips: Enter the applied load in newtons or pounds, bolt diameter in meters or inches, and plate thickness in meters or inches. All values must be positive numbers greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between bearing stress and crushing stress?
A: Bearing stress refers to contact stress between two surfaces, while crushing stress typically refers to compressive failure of a material. They are related but not identical concepts.

Q2: When is bearing stress most critical?
A: Bearing stress is most critical in thin materials, soft materials, or when high loads are applied through small contact areas.

Q3: How do I prevent bearing failure?
A: Use larger diameter fasteners, thicker plates, stronger materials, or distribute loads over larger areas to reduce bearing stress.

Q4: What are typical allowable bearing stresses?
A: Allowable bearing stresses vary by material. Steel typically allows 0.75-0.90 F_y, aluminum 0.60-0.80 F_y, and wood 200-400 psi perpendicular to grain.

Q5: Does bearing stress affect fatigue life?
A: Yes, high bearing stresses can initiate fatigue cracks at contact points, particularly in cyclically loaded structures.