Cohesion given Critical Depth for Cohesive Soil Calculator

Cohesion Formula:

\[ c = h_c \times \gamma \times (\tan(I) - \tan(\phi)) \times \cos^2(I) \]

Critical Depth (h_c):

Unit Weight of Soil (γ):

kN/m³

Angle of Inclination (I):

Angle of Internal Friction (φ):

Tolerance:

Cohesion of Soil (c):

1. What is Cohesion given Critical Depth Calculator?

Definition: This calculator determines the cohesion of cohesive soil based on critical depth, unit weight, and angle parameters.

Purpose: It helps geotechnical engineers and soil scientists evaluate soil stability and shear strength in slope stability analysis.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ c = h_c \times \gamma \times (\tan(I) - \tan(\phi)) \times \cos^2(I) \]

Where:

\( c \) — Cohesion of soil (kPa)
\( h_c \) — Critical depth (m)
\( \gamma \) — Unit weight of soil (kN/m³)
\( I \) — Angle of inclination (degrees)
\( \phi \) — Angle of internal friction (degrees)

Explanation: The formula calculates soil cohesion by considering the balance of forces at critical depth in a slope.

3. Importance of Cohesion Calculation

Details: Cohesion is crucial for determining slope stability, foundation design, and earthwork projects. It represents the soil's internal strength.

4. Using the Calculator

Tips: Enter all required parameters. Angles should be in degrees. The tolerance field (default ±5%) provides a practical range for the result.

5. Frequently Asked Questions (FAQ)

Q1: What is critical depth in soil mechanics?
A: Critical depth is the depth where the net pressure on soil particles becomes zero, often where tension cracks begin in cohesive soils.

Q2: How is angle of internal friction determined?
A: It's typically measured through direct shear tests or triaxial tests in a geotechnical laboratory.

Q3: Why include a tolerance percentage?
A: Soil properties are naturally variable, so the tolerance accounts for this inherent variability in real-world conditions.

Q4: What units should I use?
A: Use meters for depth, kN/m³ for unit weight, and degrees for angles. Result is in kPa (kilopascals).

Q5: Can this calculator be used for all soil types?
A: It's specifically designed for cohesive soils (clays). For granular soils, different calculations are needed.