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Rectangular Beam Load Calculator

Maximum Center Load Formula:

\[ P_{\text{max}} = \frac{8 \sigma I}{h L} \]

Pa
m⁴
m
m

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1. What is the Maximum Center Load Formula?

The maximum center load formula calculates the maximum load that can be applied at the center of a rectangular beam without exceeding the material's allowable stress. This is crucial for structural engineering and beam design applications.

2. How Does the Calculator Work?

The calculator uses the maximum center load formula:

\[ P_{\text{max}} = \frac{8 \sigma I}{h L} \]

Where:

Explanation: This formula calculates the maximum point load that can be applied at the center of a simply supported rectangular beam without causing failure.

3. Importance of Maximum Load Calculation

Details: Accurate maximum load calculation is essential for structural safety, material selection, and ensuring beams can support intended loads without deformation or failure.

4. Using the Calculator

Tips: Enter all values in consistent SI units. Allowable stress should be in Pascals (Pa), moment of inertia in meters to the fourth power (m⁴), and dimensions in meters (m). All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What is moment of inertia for a rectangular beam?
A: For a rectangular cross-section, \( I = \frac{b h^3}{12} \), where b is the width and h is the height of the beam.

Q2: How does beam length affect maximum load?
A: Maximum load decreases as beam length increases, as longer beams experience greater bending moments under the same load.

Q3: What factors affect allowable stress?
A: Allowable stress depends on material properties, safety factors, and application requirements. It's typically lower than the material's yield strength.

Q4: Can this formula be used for other beam types?
A: This specific formula applies to simply supported beams with center point loads. Other support conditions and load distributions require different formulas.

Q5: How does beam height affect load capacity?
A: Increasing beam height significantly increases load capacity as moment of inertia increases with the cube of height.

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