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Soil Bearing Capacity

Ultimate and allowable bearing capacity for shallow footings using Terzaghi (1943) and Meyerhof (1963) methods. Strip, square, rectangular and circular shapes with full N-factors and shape factors.

Inputs

degrees
kPa (kN/m²)
kN/m³
m
m (or =B for square)
m
typical 2.5–3.0
m below ground (large = none)
kN/m³
Methods & assumptions
  • Terzaghi (1943): qu = c·Nc·sc + q·Nq + 0.5·γ·B·Nγ·sγ. General shear failure assumed.
  • Meyerhof (1963): qu = c·Nc·sc·dc + q·Nq·sq·dq + 0.5·γ·B·Nγ·sγ·dγ (vertical loading, level ground).
  • Water table effects: full submergence below footing reduces γ to γ' = γ − γw.
  • Allowable qa = qu / FS. Net qa,net = (qu − γDf)/FS.
  • Use settlement check separately — bearing capacity alone may not control.

Results

Nc / Nq / Nγ
Shape factors sc/sq/sγ
Depth factors dc/dq/dγ
Surcharge q = γ·Df
Cohesion term
Surcharge term
Self-weight term
Ultimate qult
Allowable qa (gross)
Allowable qa,net