The History of Helical Piers

In the early 1800's, Alexander Mitchell industrialized power-installed helical foundations. These power-installed foundations were used in conjunction with the building of some lighthouses in the English tidal basin.

In the 1920's, light-load-capacity, manually installed helical screw anchors began to be used by the electric power commerce for guy wires and as anchorage for utility poles.

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In the 1950's, the electrical power commerce began to use power-driven helical screw anchors for tension loads to 36,000 pounds of guy anchorage for towers and utility poles worldwide. The traditional use of these anchors was to resist tension or guy loads.

In the 1960's, the use of helical screw anchors was extended by the electrical power commerce for guy anchorage of transmission towers with loads exceeding 100,000 pounds. Engineers were starting to witness other applications of helical screw anchors, including foundations. It became apparent that helical screw anchors could resist compression loads as well as tension loads.

In the 1970's, helical screw anchors became the preferred recipe for guying electrical transmission towers and utility poles. Load capacity connection began to be recognized as a major advantage of helical piles.

In the 1990's, helical piles became an standard recipe of providing deep foundations. Applications include, but are not petite to, foundation retrofits, new construction, marine moorings, boardwalks, group of transportation projects, and as tiebacks for all types of earth keeping systems.

Currently, the use of helical piles includes temporary and permanent earth retaining systems (tieback anchors), underpinning systems for structures field to settlement, pipeline supports, buoyancy operate for underwater pipe lines, tool mounts, street light foundations, and new building projects with soil conditions that typically would not permit suitable capacities.

In increasing to providing deep foundation solutions to residential foundations, MacLean Dixie helical piles have been used to entirely sustain a nine-story market building.

Terzaghi's normal Bearing Equation is now recognized as an sufficient recipe of predicting helical pile capacity. The standard commerce use of Terzaghi's normal Bearing Equation is coupled with torque-to-load-capacity relationships; these have proven to be two of the most foremost developments in the helical screw anchor industry.

With the wide acceptance of helical screw anchor technology, the international code council has now created industry-wide standards under Icc-Ac358. Icc-Ac358 establishes product testing and evaluation criteria for helical pile foundation underpinning systems.

These new standards will give engineers and local building code officials the potential to collate products from separate manufacturers without comparing raw materials, allowing them to select the best product for each project.

The History of Helical Piers

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