Static Cone Penetration Based Pile Capacity Calculator

Developed By:
Mohan Dangi (Gold Medalist)
Geotechnical Engineer

Input Parameters

Pile Diameter, D (m) — Diameter of pile shaft Pile Length, L (m) — Embedded pile length Average Cone Resistance Below Pile Tip, qc₀ (kN/m²) — Average cone resistance over depth 2D below pile tip Minimum Cone Resistance Below Pile Tip, qc₁ (kN/m²) — Minimum cone resistance over same 2D depth below pile tip Average Envelope Cone Resistance Above Pile Tip, qc₂ (kN/m²) — Average envelope cone resistance over 8D above pile tip Type of Soil for Skin Friction Clay Silty Clay and Silty Sand Sand Coarse Sand and Gravel Average Cone Resistance Along Shaft, qc (kN/m²) — Used for estimation of local shaft friction

Results will appear here.

Design Formulas

Parameter	Formula
Pile Tip Area	Ap = πD² / 4
Pile Shaft Area	As = πDL
Ultimate End Bearing Resistance	qu = ((qc₀ + qc₁)/2 + qc₂) / 2
Ultimate End Bearing Capacity	Qb = qu × Ap
Ultimate Skin Friction Capacity	Qs = fs × As
Ultimate Pile Capacity	Qu = Qb + Qs
Safe Pile Capacity	Qsafe = Qu / 2.5

Explanation:

• End bearing resistance is obtained from static cone penetration resistance values near the pile tip.
• Shaft friction is estimated using empirical correlations with cone resistance.
• Pile tip area and shaft area are calculated from pile diameter and length.
• Factor of safety = 2.5 has been used for safe load calculation.
• The calculator is based on IS 2911 recommendations.

Side Friction Correlation Table

Reference:

IS 2911 (Part 1/Sec 2): 2010
Design and Construction of Pile Foundations – Bored Cast In-Situ Piles.

Section B-3: Use of Static Cone Penetration Data.

Disclaimer:

This calculator is intended for preliminary estimation and educational purposes only. Results are based on empirical correlations and simplified assumptions. Final design should be verified through detailed geotechnical investigation, load testing, and professional engineering judgment.

© Mohan Dangi