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Footing Bearing Pressure

Axial load alone spreads evenly; add a moment and the pressure tilts. The check that matters is the middle third: once the eccentricity exceeds L/6 the footing lifts off at one edge, the linear pressure formula stops being valid, and bearing concentrates over a reduced triangular area.

Axial load P (kN)

Moment M (kN·m)

Footing width B (m)

Footing length L (m)

Allowable bearing (kPa)

Maximum pressure

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Minimum pressure

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Eccentricity e

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Kern limit L/6

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Contact

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Bearing check

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Service (unfactored) loads and allowable bearing pressure. Does not check settlement, sliding, overturning of the structure above, punching shear or the footing reinforcement — and allowable bearing must come from a geotechnical report, not a table.

PRELIMINARY SIZING ONLY — not a code-compliant design check. These are first-pass equations; they omit member stability, local buckling, shear and combined-stress interaction, connections, second-order effects and jurisdiction-specific factors. Codes vary by country and edition. Structural design must be performed and sealed by a qualified engineer.