Helical Pier Foundation: Difference between revisions

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*7000 ft lb torque for screwing 8" diameter helix in [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.
*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  
*Helix is .217" pipe, 3" diameter. [[Steel Weight Calculator]] sez it's 6.5 lb/ft. Nice! 3D printed with welding wire, that is a good way to produce the helix readily.
*Thus, the piers are quite affordable. The helix and couplers will be the hard part, that's where WAAM comes in.


=Examples=
=Examples=

Revision as of 23:34, 15 July 2020

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 [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 6.5 lb/ft. Nice! 3D printed with welding wire, that is a good way to produce the helix readily.
  • Thus, the piers are quite affordable. The helix and couplers will be the hard part, that's where WAAM comes in.

Examples