Helical Piles Dig in for the Future
Albert Bishop Chance constructed the world’s first practical earth anchor — the Never-Creep Anchor — in 1912. Now, more than a century later, Hubbell Power Systems Inc. proudly manufactures the CHANCE® line of products, most notably for its innovative technological answer to foundation repair: the CHANCE helical pile.
With residential remedial repair becoming a greater concern, the CHANCE helical pile was developed in the mid-1980s and was issued a helical underpinning methods patent in 1992. This all sounds well and good, but the question remains: What makes helical piles so effective?
To answer that query, let’s first start by defining a helical pile. It is a segmented, deep-foundation system with helical bearing plates (known as helices) welded to a central shaft. The load of the structure or application is primarily transferred from the shaft to the soil through these plates.
The helices don’t auger the soil but rather screw into it with minimal disruption. The helical plates rest in the piles’ first section, referred to as the “lead” or “starter” section. The lead area can consist of one to four helices but can hold more through the use of helical extension. Extensions are then added until the lead section penetrates the bearing strata and the necessary or required torque is achieved.
What Helical Piles Bring to the Table
We’ve answered the “what,” so now it’s time to understand the “why.” When sifting through all the foundation repair options, why should contractors and engineers pick helical piles instead of the rest?
The deep foundation repair market is saturated with options. Driven piles, drilled shafts, grouted tendons, auger-cast piles, belled piers, timber piles, and other methods all provide their own benefits, but helical piles have a number of compelling advantages over those choices.
Helical piles emphasize convenience. They’re pre-engineered and can be installed with common construction equipment. Plus, immediate loading applies to helical piles unlike concrete, which needs time to cure. Other benefits include ease of use in limited access sites, high water tables, and weak surface soils; no excavation or spoil removal; and year-round installation. For many sites, the lack of vibration during install is mandatory, and for many jobs, smaller crews help reduce labor costs. Best of all, helical piles are removable and reusable, and every time they are used, they have consistent and predictable results.
The CHANCE anchor evolution began with the Never-Creep Anchor. It then transitioned to the Power-Installed-Screw Anchors of the late 1950s and evolved into the Square One anchors of the 1980s. Through the years, CHANCE soil and anchor studies have resulted in the compilation and documentation of a wealth of anchor knowledge, knowledge that enables us to accurately predict anchor performance in most soils. This know-how, coupled with CHANCE engineered anchoring systems, helps ensure dependable anchoring at the lowest installed costs found anywhere.
The Future of Helical Piles
Today, we use anchors for applications that were previously unheard of: securing major gas and petroleum product pipelines, huge retaining walls, residential and commercial building foundations, guy-supported towers, solar panels, railway signals, outdoor lighting and signage, new construction, coastal elevation, moorings, and boardwalks, just to name a few.
The CHANCE Alliance Network (CAN) is the industry’s premier foundation stabilization experts. Composed of Hubbell Power Systems, exclusive CHANCE distributors, and CHANCE Certified Installers, this alliance delivers peace of mind and the assurance of quality.
The CHANCE helical pile system offers a well-recognized, extremely cost-effective alternative to other pile systems backed by more than a century’s worth of engineering experience. HPS also manufactures a wide variety of transmission, distribution, substation, OEM, and telecommunications products used by utilities. HPS research and development will continue to find new anchor applications, and the science of anchoring will continue to grow at the company’s forefront.