1. What is the Sag of Parabola Formula?

The Sag of Parabola formula calculates the vertical sag at the midpoint of a cable under uniform load. This is essential in structural engineering for designing cable-supported structures like bridges and overhead lines.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Ls \) — Sag Length of Cable (m)
• \( wb \) — Uniform Load (N/m)
• \( L \) — Span Length (m)
• \( F \) — Prestressing Force (kN)

Explanation: The formula calculates the vertical deflection (sag) at the midpoint of a cable under uniform loading conditions, considering the span length and prestressing force.

3. Importance of Sag Calculation

Details: Accurate sag calculation is crucial for structural stability, preventing excessive deflection, and ensuring proper tension distribution in cable-supported structures.

4. Using the Calculator

Tips: Enter uniform load in N/m, span length in meters, and prestressing force in kN. All values must be positive numbers greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What is the significance of uniform load in sag calculation?
A: Uniform load represents the distributed weight along the cable length, which directly affects the amount of sag in the structure.

Q2: How does span length affect the sag?
A: Sag increases with the square of the span length, meaning longer spans result in significantly more sag for the same loading conditions.

Q3: What is the role of prestressing force?
A: Prestressing force counteracts the sag by providing tension in the cable. Higher prestressing force reduces the amount of sag.

Q4: Are there limitations to this formula?
A: This formula assumes ideal conditions with uniform loading and perfect cable flexibility. Real-world applications may require additional considerations for temperature effects, wind loads, and material properties.

Q5: Can this calculator be used for bridge design?
A: While this provides a basic sag calculation, professional bridge design requires comprehensive analysis including safety factors, dynamic loads, and regulatory standards.