1. What is Coefficient of Permeability?

Definition: The Coefficient of Permeability of Soil describes how easily a liquid will move through the soil.

Purpose: It helps engineers determine the seepage rate through dams and other hydraulic structures.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( k \) — Coefficient of Permeability (m/s)
• \( Q_t \) — Discharge from Dam (m³/s)
• \( N \) — Equipotential Lines
• \( B \) — Number of Beds
• \( H_L \) — Loss of Head (m)
• \( L \) — Length of Dam (m)

Explanation: The formula calculates permeability based on seepage quantity and dam characteristics.

3. Importance of Permeability Calculation

Details: Accurate permeability estimation ensures dam safety, proper drainage design, and effective water retention.

4. Using the Calculator

Tips: Enter all required values with ±5% accuracy. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What are equipotential lines?
A: Lines connecting points with equal hydraulic potential in a flow net.

Q2: How is head loss determined?
A: It's the difference in water level between upstream and downstream.

Q3: What affects permeability coefficient?
A: Soil type, particle size, porosity, and degree of saturation.

Q4: Typical values for permeability?
A: Clay: 10⁻⁹ to 10⁻⁷ m/s, Sand: 10⁻⁵ to 10⁻³ m/s, Gravel: 10⁻³ to 10⁻¹ m/s.

Q5: Why ±5% accuracy?
A: Field measurements typically have this range of uncertainty.

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