Cantsink helical pile anchors have numerous applications in the design and installation of earth retention systems such as retaining walls, which can be categorized as one of four types: tieback, reticulated, counterfort, and buttress walls. All these types can be designed using helical piles. However, helical tieback walls probably comprise the most predominant use of these products for construction of retaining walls, such as basement walls, which are increasing in demand due to the population increase in the communities. Tiebacks are mainly designed to provide support against lateral forces created by soil and water pressure, which can cause walls to bow, crack or allow water intrusion.
The ultimate anchor capacity is determined using the same general equations for bearing capacity of a helical pile. Tieback vertical placement depends on the soil height against the wall. Cantsink recommends that they be installed close to any horizontal crack or bow in the wall. Minimum vertical and axial embedment are required to avoid a shallow mode of failure. The axial embedment requirement will vary depending on the project specifics. We recommend a minimum axial embedment of at least five times the shallowest helical bearing plate diameter beyond the potential failure plane. Our anchors are typically installed at a 10 to 15-degree angle from the horizontal.
The number of anchors needed depends on the soil type, anchor specification, and the soil loading on the adjacent properties. The most common types of anchors are concrete mixed grouted steel tendons and helical anchors. As described below, Cantsink helical piles are more cost-effective and more advantageous than grouted anchors.
Cantsink helical tieback anchors are easily and quickly installed into retained soil with readily available construction equipment and reduced labor cost. With Cantsink helical pile anchors, there is no excavation, no spoils and no need for dewatering. Cantsink helical pile anchors and earth retention systems can be installed in any weather and can maximize flexibility when changing soil conditions are encountered (they can be adjusted in the field to meet specified load resistance requirements). During helical anchor installation, torsional resistance can be used as an indication of encountered soil properties that can relate to anchor load capacities and help prevent overstress. In addition, the measured torque is used to estimate the anchor’s capacity, using the well-known capacity-torque correlation. This quality control measure will ensure more successful load tests on-site, and will save time and money. Once the installation is complete, Cantsink anchors can be tensioned immediately and tested without waiting for grout cure or grout equipment. By eliminating the cure times and the additional equipment cost associated with concrete mixed grouted tendons, using our products saves a significant amount of project time and considerable cost compared to grouting anchors. Finally, Cantsink helical pile anchors are ICC-ES approved products, which means that they are code compliant.
Cantsink products are manufactured in metro Atlanta using the company’s patented design and 100 percent recycled U.S. steel. Cantsink’s manufacturing facility is a net-zero energy operation using solar energy to power its complex. Our products are certified to perform to the highest standards established through the International Code Council (ICC). The ICC is an independent, member-focused association dedicated to developing model codes and standards.
To learn more about helical piles, sign up for Cantsink’s free webinars and receive continuing education credits through NCSEA and AIA. Find out what effective, economical helical piles can do to provide lasting stability for retaining walls.
For more information, please call (678) 280-7453 or email [email protected].