1. What is Specific Gravity of Soil Solids?

Definition: Specific Gravity (G_s) is the ratio of the density of soil solids to the density of water.

Purpose: It's a fundamental property used in soil mechanics for various calculations including void ratio, porosity, and unit weight determinations.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( G_s \) — Specific gravity of soil solids
• \( \gamma_{sat} \) — Saturated unit weight of soil (kN/m³)
• \( e \) — Void ratio
• \( \gamma_w \) — Unit weight of water (9.81 kN/m³)
• \( w \) — Water content (as decimal)

Explanation: The formula relates the saturated unit weight of soil to its specific gravity by accounting for void spaces and water content.

3. Importance of Specific Gravity

Details: Specific gravity is crucial for:

• Soil classification
• Phase relationship calculations
• Compaction quality control
• Concrete mix designs

4. Using the Calculator

Tips:

• Enter saturated unit weight in kN/m³
• Void ratio is dimensionless (typically 0.3-1.0 for soils)
• Water content should be entered as percentage (e.g., 15 for 15%)
• Water unit weight defaults to 9.81 kN/m³

5. Frequently Asked Questions (FAQ)

Q1: What's a typical range for G_s?
A: Most soils range from 2.60 to 2.80. Organic soils may be lower (1.3-1.8).

Q2: How do I measure saturated unit weight?
A: Using a saturated soil sample of known volume, measure its weight and divide by volume.

Q3: What if my water content is very low?
A: For dry soils, use a water content near zero (but the formula assumes some moisture).

Q4: Can I use this for partially saturated soils?
A: No, this formula is specifically for saturated conditions.

Q5: What's the precision of this calculation?
A: Results are typically accurate to ±5% when input values are precise.

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