1. What is Specific Gravity of Soil Solids?

Definition: Specific Gravity of Soil is an important property of soil being related to density. It's the ratio of the density of soil solids to the density of water.

Purpose: It helps geotechnical engineers understand soil composition and behavior for construction projects.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( G_s \) — Specific Gravity of Soil
• \( \gamma_{dry} \) — Dry Unit Weight of soil (kN/m³)
• \( e \) — Void Ratio (dimensionless)
• \( \gamma_{water} \) — Unit Weight of Water (9.81 kN/m³)

Explanation: The formula relates dry unit weight, void ratio, and water unit weight to determine the specific gravity of soil solids.

3. Importance of Specific Gravity Calculation

Details: Specific gravity helps in determining soil density, porosity, and void ratio which are crucial for foundation design and soil classification.

4. Using the Calculator

Tips: Enter the dry unit weight in kN/m³, void ratio (±5%), and water unit weight (default 9.81 kN/m³). All values must be ≥ 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical void ratio range?
A: Void ratio typically ranges from 0.4 to 1.0 for most soils, with ±5% variation common in measurements.

Q2: Why is water unit weight fixed at 9.81 kN/m³?
A: This is the standard unit weight of water at 4°C, though it can vary slightly with temperature.

Q3: What does specific gravity tell us about soil?
A: Higher values indicate denser mineral composition (e.g., quartz sand ~2.65), while lower values suggest organic content.

Q4: How accurate is this calculation?
A: Accuracy depends on precise measurement of dry unit weight and void ratio (±5% typical variation).

Q5: Can this be used for organic soils?
A: Yes, but organic soils typically have lower specific gravity (1.0-1.8) compared to mineral soils (2.6-2.8).

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