Evolution of the Helical Pier
by Rich Davis, Editor-in-Chief
In the 1830s, Alexander Mitchell invented an exciting new engineering technology that would be used in marine applications for many years. Throughout England, its protectorates, and in North America, the “screwpile” became a common foundation for boat moorings, lighthouses, docks and piers.
The technology changed little in the first few decades after it was created. Piers continued to be constructed of cast iron and were installed using capstan bars – and a lot of human labor. As screwpiles became more widely used in marine applications, human ingenuity eventually would enable their use on dry land.
American engineers figured out how to do it in 1889, 56 years after it was first patented in
In 1893, a new fence post was patented using a helical design, but its excitement soon ebbed. There were a couple additional modifications to the fence post anchor, but it wasn’t until 1933, when A.B. Chance patented his “Earth Anchor,” that other industries began to realize the benefits of helical piers.
Helical pier evolution was slow until the 1970s, when their popularity began to rise and new companies entered the marketplace. During the next three decades, helical pier technology dramatically improved and numerous product innovations developed.
In addition to the original round pipe, helical piers now were made with solid square bars and solid round rods. Some helical blades were beveled and not necessarily round. Engineers developed dozens upon dozens of different connections. Installers now pumped grout into round shaft helical piers for certain applications, and larger diameter piers were installed with half the torque of earlier models.
These improvements increased the usefulness of the helical pier, but they still embody the original concept Mitchell created for England’s marine industry a century and a half earlier. Today nearly 50 companies from around the globe build helical piers that are used underneath houses, mobile homes, lights and signs. They hold down or anchor items from trees to tents, and pipelines to electrical towers.
As builders and contractors become more aware of the benefits of helical piers, and their acceptance becomes commonplace, the future of this brilliant engineering technology seems even more promising.
