Tools · Preliminary sizing
Helical Pile Load Calculator
Enter the working load per pier and helix configuration to get required installation torque, ultimate capacity, and the SPT blow count the bearing soil needs.
Project Inputs
Enter your project details to calculate estimated pile capacity.
Results
| Parameter | Value | Unit |
|---|
How these numbers are calculated
- Ultimate load:
Qult = Qa × FS - Installation torque:
T = Qult ÷ Kt, Kt by pipe size - Helix area:
A = π/4 × (D² − OD²);Ah = A1 + A2 + A3 - Ultimate load capacity:
Qt = Ah × c × Nc, Nc = 9 - Soil cohesion:
c = (N ÷ 8) × 1000 psf, solved for required blow count N - Working load per foot of grade beam:
P = Qa ÷ X
What the Numbers Mean
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Desired pier load (Qa)
The working load each pier must carry, from the structural engineer’s pile schedule, before any safety factor is applied.
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Ultimate load (Qult)
The pier load multiplied by the factor of safety. Helical piles are usually designed with a factor of 2.0.
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Installation torque (T)
The torque the installer must reach so the pile is proven to carry Qult, using the pipe’s torque correlation factor (Kt). This is the number recorded on every PPS torque log.
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Blow count (N)
The standard-penetration (SPT) blow count the bearing soil needs at helix depth for this helix configuration to reach Qult. Compare it to the boring logs in the geotechnical report.
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Helix area (Ah)
Total bearing area of the helix plates with the shaft area removed. More helix area lowers the soil strength the pile needs.
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Pile spacing (X) and load per foot (P)
Spacing along the grade beam and the working load per linear foot of beam that spacing implies.
Common Questions
How accurate is this?
It is a preliminary sizing tool built on standard torque-correlation and bearing-capacity relationships. Actual capacity depends on the site soils, pile depth and installation records. A licensed engineer must confirm the design against the project geotechnical report, and load testing may be required by the code or the engineer.
What happens after I send my calculations?
You get the results and a link that reopens this exact configuration. Precision Piling Solutions reviews the configuration and, if you want, follows up with a quote and installation torque targets for the project.
Ready for a quote on a real job?
Send plans and load requirements on the contact page, or call 813-590-0601.
Email Me These Calculations
We’ll send this configuration and the results to your inbox, with a link that reopens the calculator exactly as you have it.
For preliminary sizing only. These results come from general torque-correlation and bearing-capacity relationships. They are not a design. Final pile capacity must be confirmed by a licensed engineer using the project geotechnical report, and verified in the field by installation torque records and load testing where required.
Next step
Turn the numbers into a quote
Send plans and soil data. We’ll match piles to the engineered loads and hand back a torque-documented install.