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Calculating Beam Deflection Formula

Moment-Area Theorem:

\[ \delta = \int \frac{M(x)}{E I} x dx \]

Nm
m
Pa
m⁴

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1. What is the Moment-Area Theorem?

The Moment-Area Theorem is a structural analysis method used to calculate beam deflection. It relates the bending moment diagram to the slope and deflection of a beam through integration.

2. How Does the Calculator Work?

The calculator uses the simplified moment-area formula:

\[ \delta = \frac{M(x) \cdot x}{E \cdot I} \]

Where:

Explanation: This simplified version assumes constant moment and provides an approximation of deflection at a specific point.

3. Importance of Beam Deflection Calculation

Details: Calculating beam deflection is crucial for structural design to ensure that beams don't deflect excessively under load, which could lead to serviceability issues or structural failure.

4. Using the Calculator

Tips: Enter all values in consistent SI units. Ensure positive values for all inputs. For complex loading conditions, more advanced methods may be required.

5. Frequently Asked Questions (FAQ)

Q1: When is the moment-area theorem most accurate?
A: The theorem is most accurate for beams with constant cross-section and material properties under simple loading conditions.

Q2: What are typical deflection limits for beams?
A: Building codes typically limit deflection to L/360 for live loads and L/240 for total loads, where L is the span length.

Q3: How does material affect deflection?
A: Materials with higher elastic modulus (E) will deflect less under the same loading conditions.

Q4: What if my beam has variable cross-section?
A: For beams with variable cross-section, the moment of inertia (I) becomes a function of x, requiring more complex integration.

Q5: Are there limitations to this simplified formula?
A: This simplified version assumes constant moment and doesn't account for shear deformation or complex boundary conditions.

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