What is this called?

[Rick Burkman]

Anyone know what this type of foundation stabilization structure is called? How about info on installation, etc.? Saw them today on a multi-unit condo structure that was originially built on wooden piers near Lake Superior and, apparently when the wood started to sink and rot, the building was supported by these structures.

[Rick Burkman]

I'll try attaching the photos this time! Sorry about that!

[Richard Pultar]

heliocoil

[Randy Mayo]

Rick

Richard is right, it is used to jack up and support a foundation that has settled.

[Gunnar Alquist]

I have heard them called helical piles or helical piers. I have seen these a couple of times. While they are apparently effective, I wonder about their longevity. The metal will probably rust out eventually. It seems to me that encasing them in concrete would be a good idea, but maybe too expensive.

[John Kogel]

Helical Pier Systems - Engineered Helical Pier Foundation Solutions (http://helicalpiersystems.com/)

PierTech Systems - Helical Piers and Anchors For Foundation Repair, Tie-Backs, Tilt-Up, and New Construction - Engineering (http://www.piertech.com/architects/products.htm)