Unit Weight of Soil given Stability Number for Cohesive Soil Calculator

Unit Weight of Soil Formula:

\[ \gamma = \frac{c}{S_n \times h_{cs}} \]

Unit Weight of Soil (kN/m³):

1. What is Unit Weight of Soil given Stability Number for Cohesive Soil?

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

Purpose: It helps geotechnical engineers and soil scientists analyze slope stability and soil behavior under different conditions.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ \gamma = \frac{c}{S_n \times h_{cs}} \]

Where:

\( \gamma \) — Unit weight of soil (kN/m³)
\( c \) — Cohesion of soil (kPa)
\( S_n \) — Stability number (dimensionless)
\( h_{cs} \) — Critical depth for stability number (m)

Explanation: The cohesion value is divided by the product of stability number and critical depth to determine the unit weight of the cohesive soil.

3. Importance of Unit Weight Calculation

Details: Accurate unit weight determination is crucial for slope stability analysis, foundation design, and earthwork calculations.

4. Using the Calculator

Tips: Enter the cohesion in kPa, stability number (±5%), and critical depth in meters (±5%). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is the typical range for cohesion values?
A: Cohesion values typically range from 0 kPa (for loose sands) to over 100 kPa (for stiff clays).

Q2: How is the stability number determined?
A: Stability number is determined through slope stability analysis and can vary based on slope angle and soil properties (±5% typical variation).

Q3: What affects the critical depth value?
A: Critical depth depends on soil type, moisture content, and loading conditions (±5% measurement tolerance).

Q4: What units should I use for inputs?
A: Use kPa for cohesion, dimensionless for stability number, and meters for critical depth.

Q5: How accurate are the results?
A: Results are theoretical estimates; field verification is recommended as soil properties can vary significantly.