A Practical Design Method for Energy Piles

General

🆔 Identification:

🎨 Color:

⚖️ Unsaturated unit weight γ_unsat (kN/m³):

⚖️ Saturated unit weight γ_sat (kN/m³):

⚙️ Mechanical properties

Cohesion c′ (kPa):

Peak friction angle φ_p^' (°):

Critical friction angle φ_cs^' (°):

Undrained shear strength S_u (kPa):

Elastic modulus E_s (kPa):

Poisson ratio ν:

Initial void ratio e₀:

Overconsolidation ratio OCR:

Plasticity index PI:

Pre-consolidation ratio p_c^':

Recompression line slope 𝜅:

Excess pore-water pressure Pu_excess: Yes No

🔗 Interaction factors

Frictional interaction factor R_φ:

Cohesion interaction coefficient R_c:

Softening coefficient β:

📚 Soil Library

Developed by Tuan A. Pham, Recep Akan & Farshid Vahedifard

The calculation method is based on:
Pham, T. A., & Vahedifard, F. (2025).
A practical design method for energy piles incorporating thermal–mechanical soil–structure interaction.
Canadian Geotechnical Journal, 62, 1–50.

https://dx.doi.org/10.1139/cgj-2025-0129

Base layer properties

Friction angle φ′ (°):

Cohesion c′ (kPa):

Elastic modulus E_s (kPa):

Poisson ratio ν:

Factors for end-bearing resistance calculation

Adjusted coefficient f_adj:

Bearing damage coefficient R_bf:

Displacement at elastic modulus limit S₅₀ / D_p:

Displacement at ultimate skin friction S_p / D_p:

Displacement at ultimate end-bearing resistance S_bu / D_p:

Soil name Top level (m) Bottom level (m)

Groundwater level (m) Unit weight of water (kN/m³)

Diameter D_p (m):

Total length L_p (m):

Free friction zone length L₀ (m):

Friction mobilization length L_F (m):

Effective friction coefficient K_E:

Young’s modulus E_p (kPa):

Temperature-related coefficient of overconsolidation ratio β_OCR:

Temperature-related coefficient of elastic modulus β_E:

Temperature-related coefficient of friction angle β_φ:

Temperature-related coefficient of cohesion β_c:

Volumetric thermal expansion coefficient of solid α_s (1/°C):

Volumetric thermal expansion coefficient of water α_w (1/°C):

Volumetric thermal expansion coefficient of the concrete α_c (1/°C):

Initial temperature T₀ (°C):

Current temperature T (°C):

P = % Qult

Without elastic settlement

Settlement (mm)

Skin friction resistance (kN)

End-bearing resistance (kN)

Total settlement

Elastic settlement (mm)

Total settlement (mm)

Total skin friction resistance (kN)

Total end-bearing resistance (kN)

Load (kN)	Settlement (mm) (without elastic)	Skin friction resistance (kN) (without elastic)	End-bearing resistance (kN) (without elastic)	Elastic settlement (mm)	Total settlement (mm)	Total skin friction resistance (kN)	Total end-bearing resistance (kN)	Total skin friction resistance (kN) (Layer 1)	Total skin friction resistance (kN) (Layer 2)	Total skin friction resistance (kN) (Layer 3)	Total skin friction resistance (kN) (Layer 4)	Total skin friction resistance (kN) (Layer 5)	Total skin friction resistance (kN) (Layer 6)	Total skin friction resistance (kN) (Layer 7)	Total skin friction resistance (kN) (Layer 8)

Curve	Color	Line	Marker	Width
Calculated
Measured