Structopedia · Geotech
Pile capacity calculator
Allowable Stress
Results
Ø — L = — Qs — Qb — — kN
1Pile Parameters
mm
m
Shaft perimeter Ps = —
Base area Ab = —
2Soil Profile

Define layers top-down. The bottom layer extends to any depth — no thickness needed. Shaft adhesion is integrated over each layer within the pile length. End bearing is taken from the layer containing the pile toe.

# Description Thickness
Layer thickness in metres. The bottom layer has no thickness — it extends to any depth.
 (m) 		Shaft
adhesion fs
Allowable unit shaft friction in kPa from your geotechnical report. Applied over the thickness of this layer within the pile length.
 (kPa) 		End
bearing qb
Allowable unit end bearing in kPa for this layer material, from your geotechnical report. The calculator automatically uses the value from whichever layer contains the pile toe — enter the correct value for every layer so results update correctly when pile length changes.
 (kPa) 		Include
in Qs
Uncheck to exclude this layer from shaft adhesion. The fs value is still recorded but not used — useful when the geotechnical report provides a value but advises against relying on it (e.g. fill, shrink-swell clays, disturbed zones).
3Allowable Capacity
Pile cross-section & soil profile
Shaft vs end bearing breakdown
Shaft
End
Shaft adhesion Qs End bearing Qb
Shaft adhesion Qs
—kN
Σ fs,i · Ps · Δzi
End bearing Qb
—kN
qb,toe · Ab
Total allowable capacity
—kN
Qs + Qb
4Minimum Reinforcement
Pile cross-section — plan view
Bar size
Item Working Value
5Detailed Working
Item Working Value
Shaft adhesion — layer by layer
Layer Depth
(m)		 Δz in
pile (m)		 fs
(kPa)		 Contribution
(kN)
Professional Disclaimer — This calculator estimates allowable pile capacity based on parameters entered directly from the geotechnical report. Results depend entirely on the quality and interpretation of the site investigation. All pile designs must be reviewed by a suitably qualified geotechnical engineer. The allowable values for shaft adhesion and end bearing must incorporate appropriate factors of safety as determined by the geotechnical engineer. Structopedia accepts no liability for designs arising from use of this tool.