Revision as of 23:30, 15 July 2020

Intro

Helical piers are essentially augers stuck into the ground, which serve as a foundation.

Take a 3" helical pier that can hold 12,000 lb/sf on rock or 1500 lb/sf on soft clay, with a safety factor of 2 [1].

7000 ft lb torque for screwing 8" diameter helix in [2]
note that if the pier has 2 helices, that doubles the load bearing capacity! You can stack the helices, but need enough space between the helices.
Helix is .217" pipe, 3" diameter. Steel Weight Calculator sez it's

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+=Intro=
+Helical piers are essentially augers stuck into the ground, which serve as a foundation.
+=Basic Calculations=
+Take a 3" helical pier that can hold 12,000 lb/sf on rock or 1500 lb/sf on soft clay, with a safety factor of 2 [https://helicalpileworld.com/How%20Many%20Piers.pdf].
+*7000 ft lb torque for screwing 8" diameter helix in [https://helicalpileworld.com/How%20Many%20Piers.pdf]
+*note that if the pier has 2 helices, that doubles the load bearing capacity! You can stack the helices, but need enough space between the helices.
+*Helix is .217" pipe, 3" diameter. [[Steel Weight Calculator]] sez it's
+=Examples=
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