Soil Phase Relationship Calculator
A soil with G = 2.65, void ratio 0.7 and 80 % saturation has a water content of 21.1 % and a bulk unit weight of 18.5236 kN/m³.
18.5235882352941 kN/m³
Full answer, then cut to fewer decimals (not rounded):
- 18.5235882352941 kN/m³
- 18.523588235294 kN/m³
- 18.52358823529 kN/m³
- 18.5235882352 kN/m³
- 18.523588235 kN/m³
- 18.52358823 kN/m³
- 18.5235882 kN/m³
- 18.523588 kN/m³
- 18.52358 kN/m³
- 18.5235 kN/m³
- 18.523 kN/m³
- 18.52 kN/m³
- 18.5 kN/m³
- Void ratio e
- 0.7
- Porosity n = e/(1 + e)
- 41.17647059 %
- Water content w
- 21.13207547 %
- Degree of saturation S
- 80 %
- Dry unit weight γd
- 15.29205882 kN/m³
- Saturated unit weight γsat
- 19.33147059 kN/m³
- Submerged unit weight γ′
- 9.521470588 kN/m³
- Air content nₐ = n(1 − S)
- 8.235294118 %
Step-by-step solution
- Se = wG → w = Se/G = 0.8 × 0.7 ÷ 2.65 = 0.2113207547
- γ = (G + Se)γw/(1 + e) = (2.65 + 0.56) × 9.81 ÷ 1.7 = 18.52358824 kN/m³
- γd = Gγw/(1 + e) = 15.29205882 kN/m³
Soil Phase Relationship Formula
Se = wG, γ = (G + Se)γw/(1 + e)
n = e/(1 + e), γd = Gγw/(1 + e), γsat = (G + e)γw/(1 + e), γ′ = γsat − γw
Worked Example
A soil with G = 2.65, e = 0.7 and S = 80 %:
- Se = wG → w = Se/G = 0.8 × 0.7 ÷ 2.65 = 0.2113207547
- γ = (G + Se)γw/(1 + e) = (2.65 + 0.56) × 9.81 ÷ 1.7 = 18.52358824 kN/m³
- γd = Gγw/(1 + e) = 15.29205882 kN/m³
Porosity n = e/(1 + e): 41.17647059 % · Water content w: 21.13207547 % · Degree of saturation S: 80 % · Dry unit weight γd: 15.29205882 kN/m³ · Saturated unit weight γsat: 19.33147059 kN/m³ · Submerged unit weight γ′: 9.521470588 kN/m³ · Air content nₐ = n(1 − S): 8.235294118 %
GATE tip
Draw the phase diagram with Vs = 1: then Vv = e, Vw = Se, Ws = Gγw and Ww = Seγw. Every formula on this page follows by dividing weights by volumes.
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Frequently asked questions
Which relation links water content and void ratio?
Se = wG. For a saturated soil (S = 1) it reduces to e = wG, the most used identity in soil-mechanics problems.
Why is the submerged unit weight γsat − γw?
Below the water table buoyancy acts on the soil skeleton, so effective stress uses γ′ = γsat − γw, about half of γsat.
Sources
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures .
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
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APA
Scientific Converters. (2026, October 15). Soil Phase Relationship Calculator. Retrieved October 29, 2026, from https://scientificconverters.com/calculators/soil-phase-relationship-calculator/
IEEE
Scientific Converters, "Soil Phase Relationship Calculator," scientificconverters.com. Accessed: Oct. 29, 2026. [Online]. Available: https://scientificconverters.com/calculators/soil-phase-relationship-calculator/