Terzaghi Bearing Capacity Calculator
A 2 m wide strip footing founded 1.5 m deep in sand (φ = 30°, γ = 18 kN/m³) has an ultimate bearing capacity of 950.645 kPa.
950.645023700673 kPa
Full answer, then cut to fewer decimals (not rounded):
- 950.645023700673 kPa
- 950.64502370067 kPa
- 950.6450237006 kPa
- 950.645023700 kPa
- 950.64502370 kPa
- 950.6450237 kPa
- 950.645023 kPa
- 950.64502 kPa
- 950.6450 kPa
- 950.645 kPa
- 950.64 kPa
- 950.6 kPa
- Nc
- 37.1624346
- Nq
- 22.45574162
- Nγ
- 19.13
- Overburden q = γDf
- 27 kPa
- Net ultimate qnu = qu − q
- 923.6450237 kPa
- Net safe bearing capacity qnu/FS
- 307.8816746 kPa
- Safe bearing capacity qnu/FS + q
- 334.8816746 kPa
Step-by-step solution
- qu = cNc + qNq + 0.5 γBNγ
- qu = 1 × 0 × 37.1624346 + 27 × 22.45574162 + 0.5 × 18 × 2 × 19.13
- qu = 950.6450237 kPa
Terzaghi Bearing Capacity Formula
qu = cNc + γDf Nq + 0.5γBNγ
square: 1.3cNc + qNq + 0.4γBNγ; circular: 1.3cNc + qNq + 0.3γBNγ
Worked Example
A 2 m strip footing at 1.5 m depth in sand with φ = 30° and γ = 18 kN/m³:
- qu = cNc + qNq + 0.5 γBNγ
- qu = 1 × 0 × 37.1624346 + 27 × 22.45574162 + 0.5 × 18 × 2 × 19.13
- qu = 950.6450237 kPa
Nq: 22.45574162 · Nγ: 19.13 · Overburden q = γDf: 27 kPa · Net ultimate qnu = qu − q: 923.6450237 kPa · Net safe bearing capacity qnu/FS: 307.8816746 kPa · Safe bearing capacity qnu/FS + q: 334.8816746 kPa
GATE tip
GATE questions often give the factors; switch to “Enter Nc, Nq, Nγ” so your answer uses exactly the same numbers as the key.
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Frequently asked questions
What are Terzaghi’s factors at φ = 30°?
Nc = 37.16, Nq = 22.46 and Nγ = 19.13 (Kumbhojkar’s values for Nγ, as tabulated by Das).
What is the difference between net safe and safe bearing capacity?
Net safe = (qu − γDf)/FS; safe bearing capacity adds the overburden back: qnu/FS + γDf.
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). Terzaghi Bearing Capacity Calculator. Retrieved October 29, 2026, from https://scientificconverters.com/calculators/terzaghi-bearing-capacity-calculator/
IEEE
Scientific Converters, "Terzaghi Bearing Capacity Calculator," scientificconverters.com. Accessed: Oct. 29, 2026. [Online]. Available: https://scientificconverters.com/calculators/terzaghi-bearing-capacity-calculator/