1. What is Bending Stress?

Bending stress is the internal stress induced in a material when an external bending moment is applied. For steel square tubes, it's crucial to calculate this stress to ensure the structural integrity under load.

2. How Does the Calculator Work?

The calculator uses the bending stress equation:

Where:

• \( M \) — Bending moment (foot-pounds)
• \( Z \) — Section modulus (inches³)

Explanation: The equation calculates the maximum stress at the extreme fiber of the steel tube when subjected to a bending moment.

3. Importance of Bending Stress Calculation

Details: Calculating bending stress helps engineers determine if a steel tube can withstand applied loads without yielding or failing, ensuring safety in structural designs.

4. Using the Calculator

Tips: Enter bending moment in foot-pounds and section modulus in cubic inches. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is section modulus?
A: Section modulus (Z) is a geometric property that describes a cross-section's resistance to bending. It depends on the shape and dimensions of the tube.

Q2: What are typical bending stress limits for steel?
A: For mild steel, the yield stress is typically around 36,000 psi, but always check the specific grade of steel being used.

Q3: How do I find the section modulus for my tube?
A: Section modulus can be calculated from the tube dimensions or found in engineering reference tables for standard tube sizes.

Q4: Does this calculator account for safety factors?
A: No, this calculates the actual stress. Appropriate safety factors should be applied separately based on application requirements.

Q5: Can this be used for other shapes besides square tubes?
A: The basic equation applies to any shape, but the section modulus value must be appropriate for the specific cross-section.