Bearing Capacity Factor Ngamma Calculator
Unit-weight bearing capacity factor Ngamma = 2 * (Nq + 1) * tan(phi) with Nq = tan^2(45 + phi/2) * exp(pi * tan(phi)); this is the Vesic (1973) convention, which differs from Terzaghi's and Meyerhof's original third factors. Equals 0 at phi = 0.
Description
Unit-weight bearing capacity factor Ngamma = 2 * (Nq + 1) * tan(phi) with Nq = tan^2(45 + phi/2) * exp(pi * tan(phi)); this is the Vesic (1973) convention, which differs from Terzaghi's and Meyerhof's original third factors. Equals 0 at phi = 0.
Bearing Capacity Factor Ngamma Calculator: Unit-weight bearing capacity factor Ngamma = 2 * (Nq + 1) * tan(phi) with Nq = tan^2(45 + phi/2) * exp(pi * tan(phi)); this is the Vesic (1973) convention, which differs from Terzaghi's and Meyerhof's original third factors. Equals 0 at phi = 0.
When to use Bearing Capacity Factor Ngamma
Use this geological calculation for a transparent first-pass interpretation of measured rock, soil, fluid, well, stratigraphic, isotopic, geophysical, or seismic data under an explicitly selected model.
- phi
- Friction angle phi in degrees.
How Bearing Capacity Factor Ngamma works
Unit-weight bearing capacity factor Ngamma = 2 * (Nq + 1) * tan(phi) with Nq = tan^2(45 + phi/2) * exp(pi * tan(phi)); this is the Vesic (1973) convention, which differs from Terzaghi's and Meyerhof's original third factors. Equals 0 at phi = 0. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.1
- Ngamma
- Unit-weight bearing capacity factor Ngamma (Vesic convention), dimensionless.
Limitations and assumptions
- Geotechnical correlations and idealized failure models depend on stratigraphy, sampling disturbance, drainage, stress history, groundwater, density, anisotropy, scale, construction sequence, and laboratory or field method. Site-specific design requires investigation and code factors.
- Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.
Alternative or Complementary approaches
Compare independent measurements and models, retain units and analytical metadata, propagate uncertainty, and validate interpretations against logs, cores, maps, laboratory data, or field observations.
References
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Geotechnical engineering — Wikipedia contributors
Similar or alternative tools
- Bearing Capacity Terzaghi Calculator
Ultimate bearing capacity of a shallow strip footing qu = c*Nc + q*Nq + 0.5*gamma*B*Ngamma. Factors: Nq = exp(pi*tan(phi))*tan^2(45 + phi/2), Nc = (Nq - 1)*cot(phi), Ngamma = 2*(Nq + 1)*tan(phi) (Vesic convention for Ngamma; Terzaghi's original third factor differs). Base equation without shape or depth corrections. c and q in kPa, gamma in kN/m3, B in m.
- Bearing Capacity Factor Nq Calculator
Surcharge bearing capacity factor Nq = tan^2(45 + phi/2) * exp(pi * tan(phi)), common to Terzaghi, Meyerhof and Vesic; equals 1 at phi = 0.
- Bearing Capacity Vesic Calculator
Ultimate bearing capacity with Vesic (1973) shape and depth factors: qu = c*Nc*sc*dc + q*sq*dq + 0.5*gamma*B*Ngamma*sGamma, dGamma = 1. Factors Nq = exp(pi*tan(phi))*tan^2(45 + phi/2), Nc = (Nq - 1)*cot(phi), Ngamma = 2*(Nq + 1)*tan(phi) (Vesic convention). Shape factors sc = 1 + (B/L)*(Nq/Nc), sq = 1 + (B/L)*tan(phi), sGamma = 1 - 0.4*B/L; depth factors dq = 1 + 2*tan(phi)*(1 - sin(phi))^2*Df/B and dc = dq - (1 - dq)/(Nc*tan(phi)). c and q in kPa, gamma in kN/m3, lengths in m.